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Be NEWSLETTER

NUMBER

June

EditorinChief Technical Editor

Geraldine J Peters Douglas R Gies

email g jp etersmucenuscedu email giescharagsuedu

Space Sciences Center Center for High Angular Resolution

University of Southern California Georgia State University

University Park University Plaza

Los Angeles CA Atlanta Georgia

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Contents

Editorial G Peters

Working Group Matters

Working Group News Myron Smith

Mercedes Jaschek A M Hub ert

Contributions

Short term variability of Be more problems D Baade

Line Prole Variations due to NRP Velocity and Temperature Fields

D Gies

A in the binary system CR Cas R Clement V Reglero

J Fabregat

Narrow Optical Absorption Comp onents in Lib R Hanuschik

M Vrancken

Whats Happ ening

First Results from the February Campaign on Orionis Request

for Observational Supp ort of a Second Campaign G Peters

Preliminary Rep ort of the MultiSite MultiSatellite Campaign

on Cas M Smith

Preprints Received

Bibliography

Meetings

LaTeX Template for Abstracts

The Be Star Newsletter is produced at and nancial ly supported by

the Georgia State University Department of Physics and Astronomy

The electronic version is available on

the World Wide Web httpwwwcharagsueduBeNewsintrohtml

or by anonymous ftp ftp charagsuedu cd BeNews

Be Star Newsletter

EDITORIAL

With this Issue I am sad to rep ort that Mercedes Jaschek the founder and rst editor

of the Be Star Newsletter passed away in Salamanca in late November

after a long illness Resp onding to a consensus of the members of the Working Group

on Be Stars that a newsletter would b e useful Mercedes underto ok the formation of

the Be Star Newsletter and published the rst issue in January From that time

until her resignation in she pro duced issues and established a character and

high quality for the Newsletter that we strive to maintain to day Mercedes will b e

truly missed in the Be star community and we send our condolences to her husband

Carlos and their family A summary of Mercedes career app ears in this issue

Our electronic Newsletter continues to evolve One can browse the current and recent

issues at our web site at Georgia State University andor ftp a PostScript le of the

entire Newsletter Please continue to send us your comments and suggestions for

improvement as this is the only way we can determine whether we are pro ducing a

publication that it interesting useful convenient to read and ultimately serves the

community

The problems surrounding the interpretation of the shortterm photometric and line

prole variability in Be stars are further discussed in this issue No in two con

tributions The discovery of an apparent detached binary consisting of a Be star and

a BB ob ject is also announced Transient activity observed in Be stars just might

hold the clue to the causes for the mass loss as well as dynamics in the circumstellar

disk and in this issue of the Newsletter we learn of the shortlived presence of nar

row optical absorption comp onents in Fe II in a Be and their unexp ected

b ehavior In our section Whats Happ ening we include preliminary rep orts on

multiwavelength campaigns on Cas and Ori that were carried through earlier

this year As usual we thank all who sent contributions and help ed compile the

bibliography

We plan to continue a publication frequency of two issues p er year for the immediate

future and anticipate that Issue No will go to press in Octob erNovember In

order that we can achieve a timely publication please send copies of your contributions

and abstracts to the editorinchief and technical editor by

September

Send contributions by email g jp etersmucenuscedu giescharagsuedu As men

tioned in the last Newsletter b eginning with Issue No we are requiring that

abstracts b e submitted as LaTeX les A template for their preparation is provided

in this issue and can also b e downloaded from our web site Illustrations should b e

sent by Email as a PostScript le If it is not p ossible to transmit your contribution

electronically please send or fax a dark cameraready copy

I hop e your summer is happy and pro ductive and that you consider announcing your

discoveries and new ideas in the next Be Star Newsletter

Gerrie Peters EditorinChief

Be Star Newsletter

WORKING GROUP MATTERS

Working Group News

Myron A Smith

Working Group Chairman

email BEIAUiuegtcgsfcnasagov

Congratulations to Our New and Current Be NL Editor

Following the overwhelming recommendation of the BBe Working Group and Or

ganizing Committee I have reapp ointed Gerrie Peters as Scientic Editor of the Be

Star Newsletter for the p erio d Doug Gies will remain as Technical Editor

Im sure you will all join me in congratulating Gerrie for her job over the last few

years It is also appropriate to express our appreciation to her for continuing in a job

which must at times seem frustrating and deadlinedriven

Our Aliations

Im pleased to announce that Dr Marcello Ro dono President of the IAU Commission

on Close Binary Stars C has informed me that our Working Group has b een

granted aliation status with this Commission This brings to three our aliations

the other two b eing with C Variable Stars Pres M Jerzkiewicz and C Stellar

Classication Pres H Levato Our application for aliation with C Theory of

Stellar Atmospheres has b een declined b ecause the OC did not want to attach itself

to WGs for disparate stellar groups I have attempted to make aliate our WG to

the Division of Variable and Binary Stars but the OC of this Division may not b e

ready to attach itself to WGs of particular stellar groups either There do es not seem

to b e any ocial pressure for WGs to reattach themselves at the Divisional level at

this time so I have not pursued this issue

Up coming Meetings and Nonmeetings

Im sorry to rep ort that the organizers of the informal workshop on SupraThermal

Pro cesses in Be Stars originally planned to b e held in conjunction with the AAS

meeting in Madison in June cf Be Star Newsletter No p have decided

to cancel this ad ho c meeting The announcement of this meeting was met with

enthusiasm among a number of quarters among members of our own B star Working

Group I received ab out notes from our own membership three from outside

North America and several from p eople who thought it was a go o d idea but who

could not attend However we received no resp onses at all from the members of

the AAS HEAD members with whom we would share the meetings agenda I have

not b een able to come up with an alternate site for such a meeting

I communicated with Neil Gehrels the Chair of the HEAD who was surprised himself

with this result Neil p ointed out to me that there is a strong tradition of HEAD

members preferentially attending the January meeting I conclude that this is not

the right time for a workshop on this sub ject

On a related note Dr Mike Jerzykiewicz the President of the IAU Commission on

Variable Stars C has made a request for a meeting ro om at the August IAU

Be Star Newsletter

GA meeting in Kyoto

The Passing of Dr Richard Thomas

I have b een informed that Dr Richard Nelson Thomas succumbed to a stroke on

April th One of Dicks sp ecial interests in the last several years was physics of Be

stars Many of us came of age in this eld under his intellectual shadow We mourn

his passing and will miss his passionate pursuit of scientic truth that has left its

mark on our eld

Mercedes Jaschek

At the end of November we sadly learned that Mercedes Jaschek had died

in Salamanca Spain Mercedes and Carlos Jaschek left Strasb ourg in

ocially the date of their retirement but they were still very active scientically

though in Spain now Working through till the last moment while aected by an

illness which exhausted her more day after day Mercedes gave us a real lesson of

courage

Many readers of the Be Star Newsletters know Mercedes from her work on the Be

stars the latter however represents only a fraction of her enormous scientic pro

duction a result of forty years of work conducted daily in close collab oration with

her husband Carlos Jaschek

The leading idea of Mercedes scientic work was to show constantly the fundamental

contribution of the stellar classication to the development of As a

fruitful consequence of that work dierent sp ectral subgroups were discovered and

their sp ectral p eculiarities put in evidence This has b een clearly illustrated by her

work in the eld of stellar sp ectroscopy rst in the optical range later in the UV

and IR progressing along with the acquisition of a larger number of data in these

wavelength ranges Hence one of the main preo ccupations of Mercedes Jaschek was

to develop classication metho ds adapted to each newly accessible wavelength range

Her Classication of Stars written in collab oration with Carlos Jaschek

gives an excellent review of the successive contributions of the dierent classication

systems as well as a detailed description of each stellar subgroup ranging from the

hottest to the co olest stars hence underlining the riches of information obtainable

from the stellar classication

We have to mention here for example the p ersonal works of Mercedes on the clas

sication of Be Be Hep o or Herich Ap and Am stars her discovery together

with Carlos Jaschek of the ApSi stars the rst detections of hot stars with an

anomalous CNO the dierence b etween the sup ergiants in the Magellanic Clouds and

in our All this extraordinary work was conducted in collab oration with

all over the world Starting at La Plata in her career continued

at Cordoba Perkins Yerkes in Michigan in Geneva then at Strasb ourg Observa

tory which Mercedes and Carlos Jaschek joined in In the pursuit of her work

Mercedes collab orated with sp ecialists of each technique or eld of research and most

often to o with Carlos Jaschek We are indebted to them for many precious to ols at

lases and catalogues of wide interest which will remain as reference works atlases of

stellar sp ectra in visible UV and IR catalogues of stellar sp ectral classication cat

Be Star Newsletter

alogues of sp ectral groups bibliographical catalogues all those do cuments archived

in the data base of the Strasb ourg Centre of Stellar Data particularly useful in this

era of massive data acquisition

Another activity of Mercedes and Carlos Jaschek was the organization of meetings

for working groups on dierent categories of stars cf the Journeesde Strasb ourg

They also published review articles and b o oks on sp ectral classication and on p ecu

liar stars such as Co ol Stars with Excesses of Heavy Elements M Jaschek and P

C Keenan eds The Classication of Stars C and M Jaschek eds

The Behavior of Chemical Elements in Stars C and M Jaschek eds In

most of these b o oks it is dicult to distinguish the contribution of Mercedes from

that of her husband so close was their collab oration I think however that Mercedes

was one of the few p eople maybe the only one for the time b eing who could in a few

seconds give the classication of a star by lo oking at its visible UV or IR sp ectrum

Concerning the activity of Mercedes in the eld of Be stars I have chosen to remember

here three essential asp ects of her work The rst is the sp ectroscopic survey of Be

stars in the southern hemisphere at Cordoba and La Plata b etween and

together with a catalogue and a bibliography of Be stars for the p erio d

C Jaschek L Ferrer and M Jaschek written following the same line

as the catalogues of Merrill and Burwell published b etween and The

second is the reactivation of the Working Group on Be stars during the IAU General

Assembly in Montreal the creation of our bulletin Be Star Newsletter of

which Mercedes was the successful editor till the summer of and the initiative

of the IAU Symp osium Be and Shell Stars held in Munich in for which she

was chairman of the scientic committee Finally the third is the pioneering work

done by Yvette Andrillat Mercedes and Carlos Jaschek on the determination of the

fundamental prop erties of the Be Be Ae and shell stars in the near IR

Mercedes was very enthusiastic in her research but she remained very mo dest ab out

it Praising the work of others she always made constructive and friendly comments

Many of us will remember the warm welcome Mercedes and Carlos Jaschek reserved

for their guests and colleagues

Anne Marie Hub ert

Meudon

Be Star Newsletter

CONTRIBUTIONS

Short term variability of Be stars more problems

Dietrich Baade

Europ ean Southern Observatory

KarlSchwarzschildStr

D Garching b ei M unchen

Germany

Internet dbaadeesoorg

In two recent contributions to our Newsletter No pp and Luis Balona

has drawn attention to a number of problems with the interpretation of the variabil

ity of Be stars This matter is in fact very complex and the following collection

of examples aims at identifying additional p otential pitfalls However it do es not

pretend to supply a solution of whatever kind

Mean errors

Balona Be Star Newsletter No p states that the ratio of the p erio d

of the observed line prole variability to the rotation p erio d which follows from the

assumptions made by Gies and Hahula for Eri Be Star Newsletter No p

diers by standard errors from the mean ratio of unity derived by Balona MNRAS

from a relatively large sample He implies that this is a serious failure of the

NRP mo del A minor observation is that with the standard error of following

from his earlier work MNRAS the dierence of seems to

corresp ond to only standard deviations The more salient p oint is what this means

In a more recent pap er MNRAS Balona compiles an enlarged sample

of observed photometric p erio ds P and computed rotation p erio ds P of Be

rot

stars In his analysis he concludes that P P He only provides the

rot

of the mean namely which would make Eri an case But standard error

using his values of the disp ersion of the two distributions of v values and eliminating

e

outliers with v kms one estimates a disp ersion of roughly ab out

e

their mean of unity This is and makes a big dierence

Perhaps it is p ermissible to illustrate this dierence by a trivial example namely the

height of male adults in a given region The larger the number of men is whose

height has b een measured the more accurate will b e the computed mean height In

other words the standard error of the mean will b ecome smaller and smaller with

the size of the sample For instance the numbers might b ecome mm

The practical value of this accuracy is less obvious even though it might b e easy to

improve it further by obtaining more measurements More sp ecically a man who

stands mm would deviate from the mean by roughly times the standard

error of the mean but only twice the intrinsic disp ersion of the distribution of heights

if the latter amounts to mm

Obviously if a sample has a natural disp ersion it is it which is more relevant for

the characterization of the sample as a whole and also determines the probability of

individual values For example the mean photometric p erio d and the mean rotation

Be Star Newsletter

p erio d of Be stars are not very useful physical quantities b ecause the radius of Be

stars changes by more than a factor of two from early to late sp ectral sub classes

The individual ratios of these two p erio ds form a more interesting sample The

disp ersion mentioned ab ove is signicantly less than what one would exp ect under

the hypothesis of these two p erio ds b eing uncorrelated On the other hand a

disp ersion is to o large to establish the general equality of the two p erio ds in Be stars

and therefore do es not suce as an observational conrmation of the rotational

mo dulation mo del To rely exclusively on the standard error of the mean p erio d ratio

that the two p erio ds are equal in all Be stars so makes sense only if we know already

that the mean ratio of unity has a physical meaning Such evidence do es not seem to

exist so far

Remember also that to zeroth order pulsation p erio ds dep end on the mean den

sity as P Since in this segment of the mass is roughly

puls

prop ortional to radius R this b ecomes P R If Be stars have ab out the same

puls

angular momentum p er unit mass and similar mass and rotation proles their ro

tation p erio ds will crudely follow a relation P R Since the range in R only

rot

covers a factor of if classes VI I I are considered cf Table in

Balona MNRAS a disp ersion in the ratio P P is not necessar

rot puls

ily astonishing Why the average ratio would b e so close to unity is still awaiting an

explanation But the main p oint is that at this moment the disp ersion as the more

signicant quantitity do es not identify a particular mo del and the transition from

P P to P P is not justied

rot puls rot puls

After this discussion Eris deviation of or even standard errors from the mean

p erio d ratio app ears to lack physical relevance whereas expressed as times the

disp ersion of the distribution it is absolutely normal and do es not

require sp ecic attention

Dierent distributions and distributed dierences

Balona MNRAS Fig compares two dierent reconstructions of the

distribution of equatorial rotation velocities v from two dierent samples

e

For the sample Balona MNRAS Fig the observed distribu

tion of v sin i values was statistically deconvolved under the assumption of

e

randomly oriented rotation axes

For the stars of the sample Balona MNRAS Tab indi

vidual v values were derived from the observed v sin i a sp ectral typeradius

e e

calibration the observed photometric p erio d the single or doublewave na

ture of the light curve and the assumption that the photometric p erio d is the

rotation p erio d

He concludes that the consistency of the two resulting distributions gives further

credence to the pro cedures used for deriving them

However a much simpler health check which unlike Balonas approach do es not

involve a variety of assumptions and data transformations is to test whether the two

observed v sin i distributions used as the original input for the two derived samples

are compatible As can b e seen in Fig the mean values of these two data sets dier

by A test applied to the two histograms admits the hypothesis that the two

Be Star Newsletter

FIGURE Solid line The distribution of observed v sin i values in Balonas

sample MNRAS Dashed line Ditto for Balonas sample adapted from

Fig in MNRAS

distributions were drawn from the same sample with less than probability

Furthermore the implied systematic uncertainty in the mean equatorial velocity

may b e compared with Balonas result that rotation and photometric p erio ds agree

to within with a standard error of cf ab ove

Random inclinations

Another more direct check on Balonas result is to study the geometric pro jection

factors sin i which can b e derived from his second sample ratio of columns v sin i

e

and v in Table of MNRAS The corresp onding histogram is plotted in

e

Fig where also the distribution is shown which one would exp ect from a sample

with random is and constant v

e

These Be stars constitute a randomly drawn sample although there may b e some

bias towards large inclination angles b ecause the ma jority of the variabilities was

discovered photometrically which within most of the mo dels considered would b e less

probable for p oleon stars But one would exp ect that the distribution of the implied

sin i values still b ears resemblance with a truly random sample This b eing an absolute

test it should similarly to the one made in the previous section have a higher

signicance than Balonas comparison of the distributions which were reconstructed

in dierent complex ways from two dierent samples

Even considering the p ossible bias against p oleon stars one do es not feel very com

fortable with the claim MNRAS that rotation and variability p erio ds

statistically agree to within when one realizes Fig that this conclusion is

based on sin i values which in out of stars stars with v kms were ex

e

cluded are greater than greater than still in cases Note that this census is

also a degradation with resp ect to the initial subsample in which only out of

sin i values exceeded MNRAS whereas b ecause of the increase of the

sample the standard error of the mean p erio d ratio went down from to

Balona has emphasized that there is some ambiguity b etween single and double

Be Star Newsletter

FIGURE Solid line The distribution of sin i values deduced from Balonas Table

MNRAS stars with v kms were omitted Dashed line The exp ected

e

distribution if i is random and v  v is constant

e

wave light curves He has therefore argued that the outliers with v kms

e

in his analysis of the derived v values could p ossibly b e removed if their true light

e

curves were of the doublewave type To x the sin i problem one might resort

to the inverse argument namely that the light curves of the stars concerned actually

are singlewaved which would double the estimate of the equatorial velocity But

this would mean that now stars ie of the total sample had their light

curves wrongly classied with an impact of a factor of two on the true p erio d in

every case Furthermore lo oking at the classications provided in Balonas Table

MNRAS one realizes that of the exceptional stars in his analysis are

already characterized as exhibiting a doublewave light curve and that of the other

exceptional stars are already classied as singlewave variables For the remaining

illtting stars changing the classication would remedy the primary diculty by

denition but it might well introduce the resp ective other problem

On the other hand the interpretation of Fig is quite straightforward if Balonas

assumption of the equality of rotation and photometric p erio ds is not imp osed on it

Conclusion

The path from the b ewildering multitude of observational details to an understanding

of the shortterm variability of Be stars may still b e long and lab orious The con

densation of the available information to little more than two numbers one of which

app ears ill chosen do es not lo ok like a promising shortcut To mo del the sp ectro

scopic variability is dicult But to ignore the bulk of the observational information

is even more dicult Sp ectroscopic phenomena that need to b e addressed by any

mo del include

S W

alternating broad and narrow and shap ed line proles

variability extending over full width of proles

stronger variability more p ower in the variance sp ectra in the line wings than

in the line cores

Be Star Newsletter

apparently stronger mo dulation of line proles in narrow than in broadlined

stars incl features that move from red to blue but with the same absolute

progation sp eed

frequent simultaneous presence of two or more variabilities with fairly dierent

spatial frequencies

incommensurability of multiple p erio ds in some stars but the reason may p os

sibly b e that higherorder variations are not p erio dic

Acknowledgement I thank Doug Gies for having sensitized me to the issue of the

dierent v sin i distributions and Stan Ste for useful suggestions for improvements

e

of the text

Line Prole Variations due to NRP Velocity and Tem

p erature Fields

D R Gies

CHARA Department of Physics and Astronomy

Georgia State University

Atlanta GA USA

giescharagsuedu

In the last Newsletter Balona Balona L A Be Star Newsletter

argued that that mo dels we presented for the line prole variations in Eri Gies

D R Hahula M E Be Star Newsletter are awed b ecause the

mo del underestimates the temp erature variations asso ciated with nonradial pulsations

NRP Balona p ointed out our mistake of using the observed p erio d rather than the

corotating p erio d in the derivation of radial displacement I am grateful for his

discovery of the error and I wish to show here how our results are mo died by the

correction

The longer corotating p erio d results in a larger overall radial displacement and as

p ointed out by Balona this will increase the role of temp eraturerelated ux varia

tions in the observed line prole variations Balona suggests that these temp erature

related variations overwhelm those asso ciated with NRP velocity elds so that the

latter can b e ignored However this is only true in the cases where the corotating

p erio d tends to innity ie where the observed p erio d is the rotation p erio d Balona

L A MNRAS In the case of Eri we can get a reasonable result

without insisting that the rotation and observed p erio ds are the same For example

in my numerical realization of NRP which includes Ro che distortion of the stars

shap e darkening temp erature related equivalent width variations and lo cal

temp erature variations based on radial displacements calculated using the corotating

p erio d a mo del with NRP velocity amplitudes A km s and A

r h

km s for radial and horizontal comp onents resp ectively yields a full variation of

in V and km s in centroid velocity of He I the average

velocity variations found by Bolton C T Ste S in Angular Momentum

and Mass Loss for Hot Stars ed L A Willson R Stalio Dordrecht Kluwer Aca

demic The light curve amplitude in this mo del is somewhat larger than has

Be Star Newsletter 20

15

10 NUMBER

5

0 0 100 200 300 400 500

V sin i (km s-1)

FIGURE Solid line The distribution of observed v sin i values in Balonas

sample Dashed line Statistical deconvolution of the distribution assuming random orien

tations

b een observed to mag in B but it is close enough to make the mo del

worth pursuing further

The fact that the line prole variations attain their greatest amplitude in the line

wings demonstrates that velocityrelated variations must b e more imp ortant than

temp eraturerelated variations since the variations would b e strongest in line center

if temp eraturerelated variations dominated b ecause of limb darkening Thus it is

unrealistic to assume that the line prole variations result solely from temp erature

variations in the

Finally I suggest that the case for the equality of the observed and rotational p erio ds

in Be stars is not as strong as Balona MNRAS claims Balonas

case is based on a comparison of the mean value of his derived equatorial rotational

velocities km s from the photometric p erio ds and estimated radii with the

mean equatorial velocity km s derived from a statistical deconvolution of

pro jected rotational velocities for another sample of earlytype stars Balona L A

MNRAS However the mean pro jected rotational velocity for Be

stars listed by Balona is also km s and so the actual mean equatorial

velocity without the sin i dep endence must b e signicantly larger than this A

histogram of the distribution of Balonas pro jected rotational velocities solid line

is shown in the accompanying gure together with a deconvolution based on the

assumption of random orientation dashed line using the algorithm of Lucy L B

AJ the mean of this deconvolved distribution is km s Thus

the statistical basis for claiming that the photometric p erio ds are rotational contains

a much larger systematic error than estimated by Balona

Be Star Newsletter

A Be star in the binary system CR Cas

R Clement V Reglero and J Fabregat

Departamento de Astronoma Universidad de Valencia Dr Moliner

E Burjassot Valencia Spain

We observed the detached binary system CR Cas within the framework of a uv by

and H monitoring program of low mass eclipsing binaries carried out in the past

ve years CR Cas was selected as a program ob ject on the basis of its sp ectral

classication as a G star by Leung Schneider

This system was observed in three photometric campaigns August January and

September with the m telescop e of the Centro Astronomico HispanoAleman

at the Calar Alto Observatory AlmeraSpain A one channel photometer equipp ed

with the Stromgren uv by as well as the Crawford H lters was used

The go o dquality dierential light curves we obtained cover b oth eclipses The com

parison star mesured SAO showed no variation with time We used the

ephemeris E DanielkiewiczKrosniak Kurpi nskaWiniarska

to calculate the phases In Figure we present the light curve in the y lter

FIGURE Light curve in the y lter

A rst analysis of the uv by showed that the system is actually a highly

reddened earlytype binary Clement et al Sp ectroscopic observations show

the presence of He I lines conrming this conclussion Popper

The dierential light curves show several p eculiarities The depth of the primary min

imum is variable mainly in the u lter see Figure This variability is also present

in the v and b lters and is almost nonexistent in the y lter The index is highly

variable at all phases with a disp ersion at least three times higher than the disp ersion

obtained for the other stars measured at the same time The photometric analysis

lead us to the decoupling of the contribution of b oth comp onents to the photometric

indices The uv by indices of the secondary star indicate a sp ectral type BB In

contrast the derived value is much lower than the value corresp onding to this

Be Star Newsletter

FIGURE Partial light curve in the u lter

sp ectral type indicating that the H line presents some degree of emission All the

photometric anomalies describ ed can b e explained by assuming that the secondary

star is a Be star The indices calculated for the primary comp onent are compatible

with a BV type star without any anomalies

From our photometric analysis we conclude that CR Cas is a detached binary sys

tem containig a Be star Further sp ectroscopic observations will b e very valuable to

conrm this result The detailed photometric analysis will b e published elsewhere

References

Clement R Reglero V GarcaM Fabregat J Bravo A Suso J in IAU Collo qium

Inside the Stars

DanielkiewiczKrosniak E Kurpi nskaWiniarska M International Supplement An

nuario Cracoviense No

Leung KC Schneider DP AJ

Popper DM private communication

Narrow Optical Absorption Comp onents in Lib

and M Vrancken R W Hanuschik

Astronomisches Institut RuhrUniversitat Postfach D

Bo chum rwhastroruhrunib o chumde

Koninklijke Sterrenwacht van Belgie Ringlaan B Brussel Bel

gium

We rep ort on observations of optical shell lines in Lib HR BIV esh

v sin i km s a wellknown shell star which has b een studied for decades see

Aydin Faraggiana Guo for further references

1

Based on observations obtained at the Europ ean Southern Observatory La Silla Chile at the Ob

servatoire de HauteProvence CNRS St Michel France and at the GermanSpanish Astronomy

Centre Calar Alto Spain

Be Star Newsletter

FIGURE Highresolution sp ectra of Lib in March Velocity scale is helio

centric the dotted line marks the stellar RV from the km s

The arrows in b mark interstellar absorption

In the course of our longterm sp ectroscopic survey of Be and shell stars Hanuschik et

al we have used ESOs m CoudeAuxiliary Telescope on March

equipp ed with the CoudeEchelle Sp ectrograph and a CCD The resolving p ower was

R Three further runs were p erfomed in April and May at

the m telescop e of the Observatoire de HauteProvenceFrance and in July

at the m telescop e of the GermanSpanish Astronomy Centre on Calar AltoSpain

We have measured the sp ectral region of three shell lines in Lib H Fe i i

and Na iD D

A representative prole of H on a strongly expanded scale is shown in Fig a The

prole is double p eaked with the blue p eak ux considerably lower than the red one

V R There is no smal lscale structure in the H prole nor in the He i

line Fig c

The Fe i i lines oer a completely dierent picture One such measurement is

shown in Fig b and a larger subset is seen in an expanded scale in Fig The line

prole is dominated by an asymmetric blueshifted shell feature of typical width

km s Several satellite absorption features are embedded in the central part of the

shell trough and its lowvelocity ank These will b e called narrow optical absorption

Be Star Newsletter

FIGURE Selected Fe i i sp ectra in Lib in MarchJuly Flux scale is

for the lowermost sp ectrum

components NOACs in the following

We typically count NOACs They show up in the subrange V to

hc

km s of the shell trough Their typical width is km s The NOAC with

lowest has a fullyresolved width of only km s

In nights with multiple exp osures eg March April Fig we observe slow

variability of the NOAC features b oth in RV and depth on a timescale of hours RV

changes are always such that a feature moves towards less blueshifted velocities Much

larger though are the variations of the overall app earance of the NOACs from night

to night

Since the NOACs are not visible in stellar absorption features we conclude that they

have nothing to do with NRPinduced variability Their b ehaviour esp ecially their

stationarity or drift to smal ler velocities and their o ccurrence in optical lines of low

ionization sp ecies clearly distinguishes them from the wellknown DACs in stellar

wind lines

We b elieve that we have found a new rare and transient imp ortant sp ectroscopic

phenomenon in Be star disks no such features have b een detected in our earlier

sp ectra from and The NOACs might b e due to lo cal clumps in

Be Star Newsletter

the circumstellar disk drifting across the stellar surface or they may b e asso ciated

with higherorder mo des of a density wave which causes the cyclically changing line

prole asymmetries in Lib see Hanuschik et al We strongly urge other

observers with access to a highresolution sp ectrograph to continue the time record

of these conspicuous features

References

Aydin C Faraggiana R AAS

Guo Y Inf Bull Var Stars No

Hanuschik R W Hummel W Dietle O Sutorius E AA

Hanuschik R W Hummel W Sutorius E Dietle O Thimm G AAS in

press see abstract in this Newsletter

WHATS HAPPENING

First Results from the February Campaign on

! Orionis Request for Observational Supp ort of a Sec

ond Campaign

Gerrie Peters

Space Sciences Center Univ So California

g jp etersmucenuscedu

As announced in Issue No of the Be Star Newsletter we were granted hours of

IUE observing time during the th Episo de to investigate the origin of the Discrete

Absorption Comp onents DACs in the wind in Ori B I I Ie Participants in this

pro ject include H F Henrichs D R Gies E F Guinan D McDavid and G J

Peters Photometric observations at Villanova University reveal that this star has

b een undergoing quasip erio dic outbursts every months for at least the past

years E Guinan p ersonal communication The goal was to observe the b ehavior

of the wind through two rotational p erio ds days at ep o chs of maximum and

minimum mass loss

The rst series of IUE observations of Ori b egan on Feb UT and continued

for the next hours Rep eated high disp ersion SWP images were secured throughout

this interval except for three hour interruptions when the target was earthblo cked

In total we obtained high disp ersion SWP images In order to avoid problems with

likely corrupted data we adjusted the exp osures so that the maximum DN was less

than It app eared that an exp osure time of m s worked well and insp ection

of the data conrm that it is quite go o d despite the reduced exp osure

Well I must say that we were extremely lucky in that the star apparently went into

outburst just prior to the IUE run This is astounding considering the fact that

outbursts in Ori are quasip erio dic We could not have planned it any b etter

From groundbased photometry Ed Guinan concluded that the star denitely exp e

rienced an outburst prior to the IUE run but it was a weak one b etter weak than not

at all David McDavid rep orted that the p olarization was slightly higher on Feb

Be Star Newsletter ω Orionis

5.0 ) A h (

idt 4.5 t W alen v i 4.0 Equ C IV Wind

34 35 36 Day of Year 1996

) Binned Flux -1 Bin Width: 10 A A

-1 7.0 s -2 cm rg e -10

10 6.5 ( 1450 F

34 35 36 Day of Year 1996

Fig. 1 - The EW of the C IV wind line and the flux at 1450 A versus time

during the 1996 February campaign.

Be Star Newsletter ω Orionis 1996 February 2-5

6e-10

5e-10 ) 1 - A 1 - 4e-10 s 2 - m c

g 3e-10 r e (

x SWP 56690 (max.) Flu 2e-10 Day 33 22:57 UT SWP 56712 (min.) Day 34 18:49 UT 1e-10 SWP 56725 (max.) Day 35 4:34 UT

1540 1542 1544 1546 1548 1550 1552 1554 Wavelength (A)

Fig. 2 - Representative C IV wind profiles observed at maximum

and minimum FUV light.

Be Star Newsletter

than it was in January eg pdp in the B lter was in January

and on Feb McDavids p olarimetry for this star during the past decade

indicates that in quiescence a typical value for the B p olarization is

From echelle sp ectra taken at the Ritter Observatory Chris Mulliss observed the p eak

ux and EW of the H emission to steadily increase prior to and during the IUE run

eg II and EW were on Jan on Jan

cont

on Feb on Feb on Feb and

on Feb Chris also observed the He I lines and rep orts that the

V emission in He I was stronger than the R emission during the campaign

contrary to the status in January when R V or RV Of course our exp erience

with Cen and Eri demonstrates that VR changes in the He I emission can o ccur

on a time scale of a few hours or less and it is usually the R emission that is most

variable

I have extracted the C IV Si IV and A sp ectral regions from the new IUE images

and p erformed some initial analysis of the data Plots of the C IV EW and the A

ux versus time are shown in Figure The results are interesting although the inter

pretation is not immediately obvious The C IV wind line underwent a mo dulation

of ab out in a p erio d of ab out days The depth of the second minimum was

only ab out that of the rst and it was not as welldened Insp ection of the

C IV and Si IV proles reveals that it was the p ortion of the wind b etween to

km s that varied NOT the DACs The FUV ux at A binned in A

intervals varied by only and at b est is weakly correlated with the wind strength

It should b e kept in mind that is on the average of the mean A ux Rep

resentative proles of the C IV wind lines observed at maximum and minimum light

are shown in Figure

The second IUE run also hours in duration is currently scheduled for September

As you most likely already know IUE suered a gyro failure in March ESA

will not supp ort IUE observations b eyond September I have b een informed that

Ori can b e observed with the onegyro system however We invite members of

the community to join our campaign We are esp ecially in need of groundbased

sp ectroscopic photometric and p olarimetric observations from observing sites that

have a go o d distribution in longitude If you are interested in participating in the

September campaign please contact any of the individuals mentioned ab ove

Preliminary Rep ort of the MultiSite and Multi

Satellite Campaign on Cas

Myron A Smith

CSCIUE Observatory Computer Sciences Corp oration

msmithiuegtcgsfcnasagov

Because of p ersistent rep orts of variability in Xray UV and optical wavelengths a

number of TACs were p ersuaded to grant time to monitor the prototypical Be star

Cas simultaneously The breakthrough came with orbits of nearly continuous

HSTGHRS time to b e granted to Richard Robinson and myself This allo cation

Be Star Newsletter

made it easier for our colleagues to get time at various optical sites around the glob e

plus ma jor successes in getting time with the XTE Xray Timing Explorer and IUE

satellites Robin Corb et also requested that his allo cation of ksec with ASCA b e

scheduled at the same time

For a while the schedule held together and was set for Jan However

when the XTE launch was scrubb ed at T minus seconds on December rd it no

longer b ecame p ossible to hang on to our January plans for XTE and HST time This

caused some of our plans to unravel A decision was made to split the program in

two The optical and the IUE schedules were retained in January The HSTGHRS

and XTE schedules were recongured to March th ASCA time could not b e

accommo dated successfully within either With hindsight this was a go o d decision

For example the failure of the Gyro No on IUE in early March would have prevented

us from obtaining any IUE coverage at all

The optical campaign had the usual bad trends in weather except for the SW US

Doug Gies and David Gray were weathered out completely in the eastern US During

Robinson and Smith had success at McDonald and Kitt Peak as did Hirata

Anand and Howarth LaPalma On nights either just preceding or

after observers were successful in Japan Hirata LaPalma Victoria A

Reid India and Czech Republic S Ste Meanwhile the IUE obtained sp ectra

some of which were corrupted with the DMU anomaly to a still unknown

degree

To date I am aware of the McDonald the McMath Indian and Czech data b eing

substantially pro cessed These data show clearly the progression of the migrating

subfeatures that have b ecome the hallmarks of the line prole variations of the

optical line proles of Cas

The HST and XTE data were carried out on a substantially simultaneous schedule

Cas was not in the Continuous Viewing Zone for XTE as it was for HST on

In addition Ste was able to cover the He I A line from the ground

during the HSTXTE campaign The HSTGHRS sp ectra were centered at the Si IV

A doublet In order to include b oth lines and get rapid readouts we relaxed

our sp ectral resolution to and obtained sp ectra every second The resulting

sp ectra sp ectra have an extremely high SNR and time resolution They show

features in b oth the photospheric and wind comp onents The migrating features seem

to b e visible in neighboring weak photospheric lines but p erhaps not in the Si IV lines

themselves In addition to this surfacerelated activity narrow absorption features

o ccasionally app ear at km s and accelerate into the primary DAC comp onent

over several hours

We also obtained a light curve from a continuous ux window near the lines We see

two dips in the light curve and deep resp ectively that are separated by ab out

hours The Si IV photospheric lines deep en when the star is brighter indicating

the light dips are real and due to a temp erature change The overall p erio d app ears

to b e close to hours a p erio d similar to the hours I have derived from assuming

the migrating subfeatures in optical lines are ro oted on the stars surface Lowdegree

NRP has not b een rep orted in this star b ecause there is no telltale variation in the

lines widths and velocities If the light curve dips are due to a rotation p erio d if one

Be Star Newsletter



assumes a V sin i of km s and an inclination of optical interferometery

then a stellar radius of R can b e inferred In any case now that we know

what to lo ok for I invite interested photometrists to get busy and demonstrate the

existence of a stable p erio d in optical continuum ux

PREPRINTS RECEIVED

Be Stars II MWC A

Yvette Andrillat Mercedes Jaschek and Carlos Jaschek AA submitted

We analyze sp ectroscopic CCD material obtained at the Haute Provence Observatory

We provide line identications and equivalent width measurements in the wavelength

region A Over emission features are identied and a comparison of

our results with those of other authors is provided as well as a table of all elements

which have b een identied in the ob ject The pattern of elements present is analogous

to that of Btype stars but some exceptions are noted like the absence of C Al and

Mn

We review the present knowledge of sp ectrum variability The observations indicate

that the equivalent widths of the lines of many elements vary by factors of up to

two We also provide a list of diuse interstellar features observed These features

lead to an average BV excess of ab out two magnitudes which is less than what is

exp ected for an ob ject having an interstellar of magnitudes

A Search for Multiperiodic Line Prole Variations in the Be Star Lib

M Flo quet A M Hub ert H Hub ert E JanotPacheco S Caillet NV Leister

AA accepted

micheleoquetobspmfr

High resolution high signaltonoise ratio CCD sp ectra of the Beshell star Lib

allowed the investigation of rapid variability in the photospheric He I and Mg I I

lines Though our sample was limited sp ectra over four nights Lib has

revealed itself to b e a go o d candidate to display multiperio dic sp ectroscopic variations

Three frequencies and cd have b een detected in the He I line and

seem to b e present in Mg I I though this latter strongly blended in its core with

a marked shell feature is not appropriate for this kind of study The higher frequency

cd has b een deduced from a time series analysis with two metho ds and from

a residual analysis It has b een asso ciated with a j m j sectorial g mo de

in the frame of nonradial oscillation We did not succeed in nding in our data the

most probable photometric frequency cd previously given by McDavid

and Cuyp ers et al and recently detected in the UV ux by Peters

however this photometric frequency and the lower frequency seem to b e mutually

linked

Atlas of HighResolution Emission and Shel l Lines in Be Stars I Line Proles and

ShortTerm Variability

Be Star Newsletter

RW Hanuschik W Hummel E Sutorius O Dietle and G Thimm

AAS in press accepted September

email rwhastroruhrunib o chumde

We present an atlas of highSN highresolution v km s data of Be star

emission and shell proles We have collected proles of H and of Fe i i mostly of the

transition These lines have b een selected to provide measures for the overall

emission strength and for the velocity eld in these disks We have collected data for

southern and equatorial programme stars covering the p erio d This is

the most comprehensive overview of prole shap es in Be disks

We prop ose a threedimensional scheme in which most observed proles can b e clas

sied The parameters are i inclination ii optical depth and iii the pattern of

the velocity eld

A search for shortterm variability timescales b etween ve days and a few minutes

in six stars ended with negative result Shortest observed timescale for variability is

a few days for welldeveloped disks in binary systems HR HR

The atmospheric variations of the peculiar Be star HD FS CMa

G Israelian M Friedjung J Graham G Muratorio C Rossi and D de Winter

email G Israelian garikstervubacb e

We have studied sp ectra of the p eculiar Be star HD Examination of the

Balmer wings enabled us to determine a value of log g indicating a p ossibly

luminosity class V The weak He i lines together with the Si i i and A dou

blet indicate a low rotation velocity in the order of km s which is much lower

than the previously claimed value of km s by Swings Allen We have

examined highresolution proles of the strong He i line at A and found on

one hand that we can explain the variation of the prole by the motions of clouds

some of which accreted The Balmer lines on the other hand show the presence of an

accelerated wind plus absorption by a disk seen edgeon

Be Stars I HD OY Gem

Carlos Jaschek Yvette Andrillat and Mercedes Jaschek

AA accepted

We analyze CCD sp ectroscopic material obtained at the Haute Provence Observatory

b etween and covering the wavelength region A Three hundred

twenty emission lines were measured and identied Of these ab out corresp ond to

p ermitted or forbidden lines of ionized iron Many forbidden lines of the total

are present including many classic nebular lines We also provide a comparison of

our results with those of other authors

The equivalent width measurements p ermit to follow in detail the variations of the

lines of several elements over the three years and to compare them to variations

rep orted by other authors On our material the largest variations corresp ond to

Be Star Newsletter

helium which varied by a factor of two and are not in phase with the variations of

hydrogen Many helium lines exhibit P Cyg type proles indicating strong outow

of matter from the star The lines of other elements follow either the variations of

the helium or of the hydrogen lines The radial velocity varies over the years with

an amplitude of more than km s

Be stars III MWC

Mercedes Jaschek Yvette Andrillat and Carlos Jaschek

AA accepted

We analyze sp ectroscopic CCD material obtained at the Haute Provence Observatory

We provide identications and equivalent width measurements in the wavelength

region Ab out emissions lines were measured and ab out of them

were identied A comparison of our results with those of other authors is provided

as well as a table of elements identied in the sp ectrum of this star The pattern of

elements present is analogous to that of a late Btype star but some exceptions are

noted such as the absence of Ne and Mg lines and the presence of K Cu and Zr lines

which app ear usually in later type stars

We review the little which is known concerning this ob ject and we also present a

quantitative account of the variations in equivalent widths The observations indicate

that the sp ectrum is highly variable so that in two dierent years only half of the

lines app ear on b oth sp ectra Furthermore variations by at least a factor of two in

the equivalent widths are present in many lines The radial velocity derived from

the emission lines km s corresp onds to that of the shell which probably has a

velocity of ab out km s with resp ect to the underlying star

Long and shortterm variability in Ostar winds I Time series of UV spectra for

bright O stars

L Kap er HF Henrichs JS Nichols LC Sno ek H Volten and GAA Zwartheod

An atlas of time series of sp ectra is presented for bright O stars The

sp ectra were obtained with the International Ultraviolet Explorer during seven ob e

seving campaigns lasting several days over a p erio d of years The UV P Cygni lines

in out of studied stars exhibit a characteristic pattern of variability in the form

of discrete absorption comp onents DACs migrating through the absorption troughs

on a timescale of a day to a week This pattern is signicantly dierent for each star

but remains relatively constant during the time span of our observations for a given

star A quantitative evalution of the statistical signicance of the variabililty is given

The winds of a number of stars app ear to vary over the full range of wind velocities

from km s up to velocities exceeding the terminal velocity v of the wind as

1

measured by the asymptotic velocity reached by DACs The amplitude of variability

reaches a maximum at ab out v in the unsaturated resonance lines of stars

1

showing DACs In saturated resonance lines we nd distinct changes in the steep

blue edge This edge variability is also found although with smaller amplitude in

unsaturated resonance lines The sub ordinate line of N IV in Per shows weak

absorption enhancements at low velocities in the blueshifted absorption that are

Be Star Newsletter

clearly asso ciated with the DACs in the UV resonance lines

We interpret these three manifestations of variation as reecting a single phenomenon

The DACs are the conspicuous form of the variability The changes at the edge can

often b e interpreted as DACs but sup erp osed on a saturated underlying wind prole

in many cases however at the same time two or more absorption events in dierent

stages of their evolution can b e identifed in the unsaturated proles hamp ering a

detailed interpretation of the edge variability The low velocity absorption enhance

ments in the sub ordinate lines are the precursors of DACs when they are formed close

to the star

The constancy of the pattern of variability over the years and the quasip erio dic

recurrence of DACs strongly suggest that rotation of the star is an essential ingredient

for controlling wind variability The observation of lowvelocity variations in sub or

dinate lines which are supp osedly formed at the based of the indicate

an origin of wind variability close to or at the photosphere of the star

The Atypical BeXRay X Persei

P Saraswat T Mihara M Matsuoka

Email priyacrabrikengojp

The Be star binary Xray pulsar was observed by ASCA on two o ccasions in

February and March The intrinsic source luminosity in the keV energy

band is ergs s The sp ectrum can b e describ ed by a p ower law with

an exp onential cuto at higher energies However the value of the cuto energy

which is much lower than the canonical value seen in the other binary is

variable and correlated with the photon index The present observations also reveal

for the rst time the presence of a soft blackbo dy emission from the

surface The features can b e naturally explained if the accreting gas is thermalized in

a strong collisionless sho ck a few stellar radii ab ove the surface of the neutron star

The radition which is mainly dominated by cyclotron line emission originates over

a range of magnetic eld values giving rise to a variable photon index and cuto

energy The Xray emission emerges in a fan b eam part of which is repro cessed by

the neutron star surface as a soft blackbo dy comp onent The timing analysis shows

that the spindown episo de since is continuing and a pulse p erio d of sec

was obtained

Dynamic Processes in Be Star Atmospheres IV Common Attributes of Line Prole

Dimples

Myron A Smith K Plett C M Johns G S Basri J Thomson and J P Aufden

b erg

ApJ accepted

email msmithiuegtcgsfcnasagov

Dimples are transient central absorption features anked by weak emissions com

monly seen in the He I line prole of the mild Be star Eri Smith and Polidan

Be Star Newsletter

have found that these features can b e repro duced with a mo del in which line photons

are scattered within an optically thick in the line slab elevated over the surface of

a rapidly rotating star We have undertaken a series of simultaneous He I multiline

observations of this star at the McMath McDonald Lick David Dunlap and Rit

ter to search for dimples in weak blue He I lines when they app ear in

Four dimples were found during hours of multiobservatory monitoring In

three cases a dimple was observed in a weak blue line of the same absorption series as

In the fourth instance a dimple was observed only in and lines

which like are strong and have weak wings A joint IUEoptical campaign

demonstrated that the He II line shows weak emission just as new dimples

app ear in the line

Our observations conrm a previous rep ort that dimples app ear in the line

of four other Be stars We also nd that the resonance C IV double weakens when

dimples app ear a result similar to that found for Eri Our data also disclosed that

migrating subfeatures similar to those found in Cas are present in the line

of the B star HR These features app ear to b e a more vigorous form of dimple

activity than observed in Eri and other mild Be stars These ndings lend strong

supp ort to the slab mo del for the dimple phenomenon They also suggest that this

activity is endemic to the class of mild Be stars The app earance of dimples in the

weak blue He I lines suggests slab masses of at least M for most dimples

The greatest enigma that characterizes classical Be stars is their highly variable and

episo dic mass loss histories Our estimates of dimpleslab masses are high enough that

this problem may b e removed if the magnetic paradigm for Be activity is correct In

this picture exospheric ares trigger explosive ablations of plasma from the upp er

photosphere The evaporated mass is trapp ed by overlying closed magnetic eld

lo ops where it co ols taking on characteristics of prominencelike structures If the

lo ops were op ened for any reason this mass would b e free to escap e from the star at

a rate consistent with mass loss rates during active Be episo des Then the essential

dierence b etween Be stars in active and inactive phases would b e understo o d not as

a dierence in their mass release rates but rather in the prevailing geometries of their

surface elds

Rapid photometric and spectroscopic variability of the Be star DX Eri

S Ste and L A Balona

AA accepted

We present results of nearly simultaneous monitoring of uvby light and He I

nm lineprole variations of the equatorial Be star DX Eri in November They

are analyzed along with numerous uvby photometry in the p erio d

The brightness of DX Eri varies on three distinct time scales The time scales of the

rapid and mediumterm variations dier by a factor of ten and can only b e separated

if the time resolution is suciently high and if the phase is well covered Our data

meet these conditions on four observing seasons The p erio d of the rapid variation

derived from data spanning almost ten years is d Due to the complex nature

of the variability we cannot decide whether the p erio d is secularly stable on a time

scale of years or whether it varies within a few p er cent from season to season The

Be Star Newsletter

light curve is slightly nonsinusoidal with a shallow light maximum at approximately

P m m

after light minimum It has an average p eaktop eak amplitude of l

in all passbands The u b c and b y indices vary with the same p erio d but with

m

amplitudes lower than and varying from season to season The m index is

constant within the errors The star is bluest in u b near light maximum

The radial velocity RV of He I nm as measured in the line wings exhibits

a sinusoidal variation with a p erio d which is the same as the photometric p erio d

of d and with an amplitude of km s The rst moment of the line prole

has a somewhat lower amplitude and larger scatter More data of b etter quality are

needed to conrm the phasedep endent variations of equivalent width FWHM and

line depth of He I nm The shap e of the RV curve diers signicantly from

P P

the light curve The RV minimum o ccurs at and the maximum at after

light minimum

The light and loworder lineprole variations are compared with those of Cen

Ste et al The observations are discussed in terms of nonradial pulsation

rotational mo dulation and binarity None of these mo dels is able to explain the

observed light colour and radial velocity amplitudes

The formation of rapidly rotating Btype stars in general Be stars in particular

through close binary evolution in the Galaxy and in the Magel lanic Clouds

J Van Bever and D Vanbeveren

Using recent evolutionary computations of intermediate mass close binaries we es

timate the number of Btype binaries with sub dwarf companions and

neutron star companions in regions of continuous and in starburst re

gions in the Galaxy and in the Magellanic Clouds Linking p ossible fast rotation of

the mass gainers in interacting binaries to the formation of disks during mass trans

fer we further predict the number of fast rotating Btype stars formed through close

binary evolution We then critically evaluate the observed rotational velocity distri

butions of Be stars Bn stars and normal Btype stars We conclude that on the

average Be and Bn stars rotate at of their break up velocity whereas there are

at least as many normal Btype stars with the same rotational velocity distribution

as Be and Bn stars Comparison b etween the theoretically predicted and observed

number of rapid rotators in general and Be stars in particular in regions of continuous

star formation and in starbursts in the Galaxy and in the MCs forces us to conclude

that only a small p ercentage of all Be stars is formed through close binary evolution

ie less than and p ossibly as low as

Be Star Newsletter

BIBLIOGRAPHY

compiled by D R Gies A M Hub ert J Jugaku G J Peters

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Evolution of the Circumstellar Shell of Pleione

BALLEREALL D CHAUVILLE J ZOREC J ApSS

Tests of the Pulsation and Starsp ot Mo dels for the Periodic Be Stars

BALONA LA MNRAS

Identication of the Soft XRay Excess in Cygnus X with Disc Emission

BALUCINSKACHURCH M BELLONI T CHURCH MJ HASINGER G

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Light Variations of the B Star HR

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The Discovery of H Emission in V Cas

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Observations of EmissionLine Stars with IR Excesses II Multicolor Photometry of

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MUKANOV DB SHEJKINA TA AAS

Inhomogeneities in the Circumstellar Envelope of the AOe Herbig Star AB Aur

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Stellar Wind and Keplerian Disk Interactions in Hot Stars abstract

BJORKMAN JE WOOD K BAAS

First Lo ok at New WUPPEAstro Observations of Hot Stars abstract

BJORKMAN KS CODE AD MEADE MR BABLER BL ZELLNER NE

ANDERSON CM EDGAR RJ FOX GK JOHNSON JJ NORDSIECK

KH SANDERS WT WEITENBECK AJ LUPIE OL SCHULTELADBECK

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Rotation Winds and Active Phenomena in Herbig AeBe Stars

BOHM T CATALA C AA

Toward a Consistent Mo del of the BIVesdO Binary Persei

BOZIC H HARMANEC P HORN J KOUBSKY P SCHOLZ G McDAVID

D HUBERT AM HUBERT H AA

Be Star Newsletter

Expanding Atmospheric Mo del Including a I I Be Stars Centerto

Limb Variation of the Emergent Intensity

CIDALE LS VAZQUEZ AC ApJ

Wisconsin Ultraviolet PhotoPolarimeter Exp eriment A First Rep ort of Observations

and Preliminary Results from the Astro Mission abstract

CODE AD ANDERSON CM BABLER BL BJORKMAN K S EDGAR

RJ FOX GK JOHNSON JJ MEADE MR SANDERS WT WEITEN

BECK AJ ZELLNER NE LUPIE OL BAAS

Be Stars with Small Discs Structure and Dynamics

COTE J WATERS LBFM MARLBOROUGH JM AA

Colour and Light Variations of Pleione b etween the Be and Shell Phases

CRAMER V DOAZAN V NICOLET B DE LA FUENTE A BARYLAK

M AA

The Equatorial Expansion of Be Stars A ThinLine Wind

DE ARAUJO FX ApSS

The Evolution of Case B Intermediate Mass Close Binaries with Galactic and Mag

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DE LOORE C VANBEVEREN D AA

HEXE Observations of Cygnus X

DOBEREINER S ENGLHAUSER J PIETSCH W REPPIN C TRUMPER

J KENDZIORRA E KRETSCHMAR P KUNZ M MAISACH M STAUBERT

R EFREMOV V SUNYREV R AA

H Emission from PreMain Sequence Stars

FERNANDEZ M ORTIZ E EIROA C MIRANDA LF AAS

Photometric Observations of PreMain Sequence Ob jects

FERNANDEZ M AAS

Gas around Pictoris an Upp er Limit on the HI Content

FREUDLING W LAGRANGE AM VIDALMADJAR A FERLET R

FORVEILLE T AA

On the Ionization Structure of HI I Regions in Stellar Envelopes with an Outward

Density Decrease

GRACHEV SI AA

The Pictoris Phenomenon among Young Stars I I UV Observations of the Herbig

Ae Star UX Orionis

GRADY CA PEREZ MR THE PS GRININ VP DE WINTER O JOHN

SON SB TALAVERA A AA

The Iron Abundance of Iota Herculis from Ultraviolet Iron Lines abstract

GRIGSBY J MULLISS C BAER G BAAS

Xray Emission from the PSR B System Near Apastron

GREINER J TAVANI M BELLONI T ApJL L

Be Star Newsletter

Be Phenomenon Extending to Lower in the Magellanic Clouds

GUMMERSBACH CA ZICKGRAF FT WOLF B AA

A Sp ectroscopic and Photometric Study of the BeShell Star Tauri

GUO Y HUANG L HAO J CAO H GUO Z GUO X AAS

ROSAT Observations of the LMC BeXRay Binary EXO the Long

term Variability

HABERL F DENNERL K PIETSCH W AA LL

Orbital Elements of Multiple Sp ectroscopic Stars

HADRAVA P AAS

NearInfrared Photometric Observations of Be Stars

HANG HR ZANG ZY PPMO

Observation of a VR Transition in the Be Star Oph

HANUSCHIK RW STEFL S HUMMEL W VRANCKEN M IBVS

No

The Detection of Narrow Absorption Comp onents NACS in FX Lib Lib

HANUSCHIK RW VRANCKEN M IBVS No

NonAxisymmetric Be Star Circumstellar Disks

HUMMEL W VRANCKEN M AA

Extended Wings of the UV Si IV C IV Resonance Doublet and the Complex Fe I I

Proles of P Cygni

ISRAELIAN G AA

Study of Variability of the Polarization in Herbig AeBe Stars

JAIN SK BHATT HC AAS

Wray GX A Hyp ergiant with Pulsar Companion

KAPER L LAMERS HJGLM RUYMAEKERS E VAN DEN HEUVEL

EJP ZUIDERWIJK EJ AA

XRay Detection of PSR B at Periastron

KASKI VM TAVANI M NAGASE F HIRAYAMA M HOSHINO M AOKI

T KAWAI N ARONS J ApJ

MultiBand Polarimetry of Be Stars I X Persei

KUNJAYA C HIRATA R PASJ

Observations of the Binary Accreting Pulsar Vela X with the SIGMA Telescope

LAURENT P PAUL J DENIS M BALLET J SCHMITZFRAISSE MC

OLIVE JC BOUCHET L ROQUES JP SUNYAEV R CHURASOV E

GILFANOV M KHAVENSON N DYACHKOV A NOVIKOV B CHULKOV

I SUKHANOV K AA

Submm Observations of Herbig AeBe Systems

MANNINGS VG ApSS

A Mysterious Line in the Sp ectrum of P Cygni

MARKOVA N AA

Be Star Newsletter

P CygniSp ectral Atlas with Complete Line Identications in the Wavelength Range

from to A

MARKOVA N ZAMANOV R AAS

Possible Low Amplitude Light Variations of DI Her

MARSHALL JJ GUINAN EF McCOOK GP IBVS No

Variable Polarization of the Be Star Lambda Eridani abstract

McDAVID D FRUEH M BAAS

Sp ectroscopic Monitoring of the Be Star HD abstract

MORRISON ND BEAVER M BAAS

The Radial Velocity Variations in Iota Herculis abstract

MULLISS CL MORRISION ND BAAS

Mass Loss from HI Infrared Lines in Herbig AeBe Stars

NISINI B MILILLO A SARECENO P VITALI F AA

UltravioletVisible Sp ectrop olarimetry of Interacting Binaries by WUPPE and Wis

consin Pine Blu Observatory abstract

NORDSIECK KH FOX GK CODE AD ANDERSON CM BABLER BL

BJORKMAN KS EDGAR RJ JOHNSON JJ LUPIE OL MEADE MR

SANDERS WT WEITENBECK AJ ZELLNER NE HAROLD J SCHULTE

LADBECK RE CLAYTON GC BAAS

Photometric Studies of Be Star Variability

PERCY JR ExpAst

Structural Peculiarities of Circumstellar Envelopes of the Young AOe Herbig Stars

POGODIN M ApSS

Discovery of an XRay Pulsar in the LMC

SCHMIDTKE PC COWLEY AP McGRATH TK ANDERSON AL

PASP

Variable Extinction in the Herbig AeBe Star HD

SITKO ML HALBEDEL EM LAWRENCE GF SMITH JA YANOW K

ApSS

Statistical Results from a JCMT Survey of mm and Submm Emission in Herbig

AeBe Stars

SKINNER S BROWN A DENT WRF ApSS

Comparison b etween a Radiative Wind Mo del for Be Stars and High Angular Reso

lution Data from the GIT Interferometer

STEE P ApSS

The Enigmatic Flarings of HR

STERKEN C MANFROID J AA

Prole Analysis of He I in Orionis Rotation and He Abun

dance

TAKEDA Y SADAKANE K TAKADAHADAI M PASJ

Be Star Newsletter

On the Abundances of and Sulfur in LateB through F Sup ergiant Atmo

spheres

TAKEDA Y TAKADAHIDAI M PASJ

The Peculiar Population of Hot Stars at the Galactic Center

TAMBLYN P RIEKE GH MURRAY HANSON M CLOSE LM McCARTHY

DW Jr RIEKE MJ ApJ

An XRay Outburst from the Radio Emitting XRay Binary LSI

TAYLOR AR YOUNG G PERACAULA M KENNY HT GREGORY

PC AA

Double Circumstellar Disc Structure in X Persei

TARASOV AE ROCHE P MNRAS LL

Hydrogen Recombination Lines in MWC

THUM C STRELNITSKI VS MARTINPINTADO J MATTHEWS HE

SMITH HA AA

Dust Shells of Distant Young Stars

TOVMASSIAN HM NAVARRO SG TOVMASSIAN GH CORRAL LJ

ApSS

On the Optical Variability of a Be Star HDE The Optical Conterpart of

the Transient Xray Pulsar A

TRUNKOVSKY EM SSRv

Conclusions ab out Disk Geometries in a Few Herbig AeBe Stars abstract

VAIDYA A SCHULTELADBECK RE BAAS

The Photometric Behaviour of the Peculiar Be Star HD

VAN DEN ANCKER ME DE WINTER D THE PS ApSS

Sp ectroscopy of HD and the Mass of Vela X

VAN KERKWIJK MH VAN PARADIJS J ZUIDERWIJK EJ HAMMER

SCHLAG HENSBERGE G KAPER L STERKEN C AA

Circumstellar Matter

WATT GD WILLIAMS PM Kluwer Academic Publishers

X Persei

ZAMANOV RK ZAMANOVA VI IBVS No

XRay Emission as a Tracer of Circumstellar Matter around Herbig AeBe Stars

ZINNECKER H PREIBISCH T ApSS

Be Star Newsletter

MEETINGS

July

Variable Stars and the Astrophysical Returns of Microlensing Sur

veys th IAP Astrophysics Collo quiumEARA Astrophysics Meeting Paris

France

Contact Mme Colette Douillet at IAP Email iap colliapfroriap coll

WWW httpwwwiapfr

January

Fundamental Stellar Prop erties The Interaction Between Observa

tion and Theory A Meeting to Mark the th Birthday of Emeritus Prof

R Hanbury Brown University of Sydney Australia

Contact Dr AJ Bo oth School of Physics A University of Sydney NSW

Australia Tel please note from August

Fax please note from August

June

A Half Century of Stellar Pulsation Interpretations A Tribute to

Arthur N Cox Los Alamos NM Contact Joyce A Guzik Los Alamos

National Lab oratory

Email joylanlgov

August

XXI I Ird General Assembly of the International Astronomical Union

Kyoto Japan

Contact Constanze la Dous Email iauiapfr

See WWW site httpcadcwwwdaonrccameetingsmeetingshtml for more

LATEX TEMPLATE FOR ABSTRACTS

begincenterLargebf Title

endcenter

centerlinebf A Author and B Author

footnotesize Institute One and Address

Institute Two and Address

vspacemm Text of abstract

bf Accepted by or Submitted to JOURNAL

it For preprints contact your electronic address

please indicate if the manuscript is available by anonymous ftp

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