ASTRONOMY and ASTROPHYSICS Gas Cooling Within the Diffuse ISM
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The Herschel⋆ Virgo Cluster Survey
A&A 545, A75 (2012) Astronomy DOI: 10.1051/0004-6361/201219689 & c ESO 2012 ! Astrophysics The Herschel! Virgo Cluster Survey XI. Environmental effects on molecular gas and dust in spiral disks!! C. Pappalardo1,S.Bianchi1,E.Corbelli1,C.Giovanardi1,L.Hunt1,G.J.Bendo6,A.Boselli4,L.Cortese5, L. Magrini1,S.Zibetti1,S.diSeregoAlighieri1,J.Davies2,M.Baes3,L.Ciesla4,M.Clemens7,I.DeLooze3,J.Fritz3, M. Grossi8,M.Pohlen2,M.W.L.Smith2,J.Verstappen3,andC.Vlahakis9 1 Osservatorio Astrofisico di Arcetri – INAF, Largo E. Fermi 5, 50125 Firenze, Italy e-mail: [email protected] 2 Department of Physics and Astronomy, Cardiff University, The Parade, Cardiff,CF243AA,UK 3 Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281 S9, 9000 Gent, Belgium 4 Laboratoire d’Astrophysique de Marseille – LAM, Université d’Aix-Marseille & CNRS, UMR 7326, 38 rue F. Joliot-Curie, 13388 Marseille Cedex 13, France 5 European Southern Observatory, Karl-Schwarzschild-Strasse 2, 85748 Garching bei Munchen, Germany 6 Jodrell Bank Centre for Astrophysics, Alan Turing Building, School of Physics and Astronomy, University of Manchester, Manchester, M13 9PL, UK 7 Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, 35122 Padova, Italy 8 CAAUL, Observatorio Astronomico de Lisboa, Universidade de Lisboa, Tapada de Ajuda, 1349-018 Lisboa, Portugal 9 Joint ALMA Office, Alonso de Cordova 3107, Vitacura, Santiago, Chile / European Southern Observatory, Alonso de Cordova 3107, Vitacura, Casilla 19001, Santiago 19, Chile Received 25 May 2012 / Accepted 10 July 2012 ABSTRACT Aims. We investigate the dust-to-gas mass ratio and the environmental effects on the various components of the interstellar medium for a spatially resolved sample of Virgo spirals. -
The Herschel Virgo Cluster Survey. XI. Environmental Effects On
Astronomy & Astrophysics manuscript no. Pappalardo˙v3 c ESO 2018 October 29, 2018 The Herschel? Virgo Cluster Survey XI. Environmental effects on molecular gas and dust in spiral disks?? Ciro Pappalardo1, Simone Bianchi1, Edvige Corbelli1, Carlo Giovanardi1, Leslie Hunt1, George J. Bendo6, Alessandro Boselli4, Luca Cortese5, Laura Magrini1, Stefano Zibetti1, Sperello di Serego Alighieri1, Jonathan Davies2, Maarten Baes3, Laure Ciesla4, Marcel Clemens7, Ilse De Looze3, Jacopo Fritz3, Marco Grossi8, Michael Pohlen2, Matthew W. L. Smith2, Joris Verstappen3, Catherine Vlahakis9 1 Osservatorio Astrofisico di Arcetri - INAF, Largo E. Fermi 5, 50125 Firenze, Italy e-mail: [email protected] 2 Department of Physics and Astronomy, Cardiff University, The Parade, Cardiff, CF24 3AA, UK 3 Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281 S9, B-9000 Gent, Belgium 4 Laboratoire dAstrophysique de Marseille - LAM, Universite´ d’Aix-Marseille & CNRS, UMR7326, 38 rue F. Joliot-Curie, 13388 Marseille Cedex 13, France 5 European Southern Observatory, Karl-Schwarzschild-Strasse 2, D-85748 Garching bei Munchen, Germany 6 Jodrell Bank Centre for Astrophysics, Alan Turing Building, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL 7 Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, 35122 Padova, Italy 8 CAAUL, Observatorio Astronomico de Lisboa, Universidade de Lisboa, Tapada de Ajuda, 1349-018, Lisboa, Portugal 9 Joint ALMA Office, Alonso de Cordova 3107, Vitacura, Santiago, Chile / European Southern Observatory, Alonso de Cordova 3107, Vitacura, Casilla 19001, Santiago 19, Chile ABSTRACT Aims. We investigate the dust-to-gas mass ratio and the environmental effects on the various components of the interstellar medium for a spatially resolved sample of Virgo spirals. -
IRAC Near-Infrared Features in the Outer Parts of S4G Galaxies
Mon. Not. R. Astron. Soc. 000, 1{26 (2014) Printed 15 June 2018 (MN LATEX style file v2.2) Spitzer/IRAC Near-Infrared Features in the Outer Parts of S4G Galaxies Seppo Laine,1? Johan H. Knapen,2;3 Juan{Carlos Mu~noz{Mateos,4:5 Taehyun Kim,4;5;6;7 S´ebastienComer´on,8;9 Marie Martig,10 Benne W. Holwerda,11 E. Athanassoula,12 Albert Bosma,12 Peter H. Johansson,13 Santiago Erroz{Ferrer,2;3 Dimitri A. Gadotti,5 Armando Gil de Paz,14 Joannah Hinz,15 Jarkko Laine,8;9 Eija Laurikainen,8;9 Kar´ınMen´endez{Delmestre,16 Trisha Mizusawa,4;17 Michael W. Regan,18 Heikki Salo,8 Kartik Sheth,4;1;19 Mark Seibert,7 Ronald J. Buta,20 Mauricio Cisternas,2;3 Bruce G. Elmegreen,21 Debra M. Elmegreen,22 Luis C. Ho,23;7 Barry F. Madore7 and Dennis Zaritsky24 1Spitzer Science Center - Caltech, MS 314-6, Pasadena, CA 91125, USA 2Instituto de Astrof´ısica de Canarias, E-38205 La Laguna, Tenerife, Spain 3Departamento de Astrof´ısica, Universidad de La Laguna, 38206 La Laguna, Spain 4National Radio Astronomy Observatory/NAASC, Charlottesville, 520 Edgemont Road, VA 22903, USA 5European Southern Observatory, Alonso de Cordova 3107, Vitacura, Casilla 19001, Santiago, Chile 6Astronomy Program, Department of Physics and Astronomy, Seoul National University, Seoul 151-742, Korea 7The Observatories of the Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 91101, USA 8Division of Astronomy, Department of Physics, University of Oulu, P.O. Box 3000, 90014 Oulu, Finland 9Finnish Centre of Astronomy with ESO (FINCA), University of Turku, V¨ais¨al¨antie20, FIN-21500 Piikki¨o 10Max-Planck Institut f¨urAstronomie, K¨onigstuhl17 D-69117 Heidelberg, Germany 11Leiden Observatory, Leiden University, P.O. -
And Ecclesiastical Cosmology
GSJ: VOLUME 6, ISSUE 3, MARCH 2018 101 GSJ: Volume 6, Issue 3, March 2018, Online: ISSN 2320-9186 www.globalscientificjournal.com DEMOLITION HUBBLE'S LAW, BIG BANG THE BASIS OF "MODERN" AND ECCLESIASTICAL COSMOLOGY Author: Weitter Duckss (Slavko Sedic) Zadar Croatia Pусскй Croatian „If two objects are represented by ball bearings and space-time by the stretching of a rubber sheet, the Doppler effect is caused by the rolling of ball bearings over the rubber sheet in order to achieve a particular motion. A cosmological red shift occurs when ball bearings get stuck on the sheet, which is stretched.“ Wikipedia OK, let's check that on our local group of galaxies (the table from my article „Where did the blue spectral shift inside the universe come from?“) galaxies, local groups Redshift km/s Blueshift km/s Sextans B (4.44 ± 0.23 Mly) 300 ± 0 Sextans A 324 ± 2 NGC 3109 403 ± 1 Tucana Dwarf 130 ± ? Leo I 285 ± 2 NGC 6822 -57 ± 2 Andromeda Galaxy -301 ± 1 Leo II (about 690,000 ly) 79 ± 1 Phoenix Dwarf 60 ± 30 SagDIG -79 ± 1 Aquarius Dwarf -141 ± 2 Wolf–Lundmark–Melotte -122 ± 2 Pisces Dwarf -287 ± 0 Antlia Dwarf 362 ± 0 Leo A 0.000067 (z) Pegasus Dwarf Spheroidal -354 ± 3 IC 10 -348 ± 1 NGC 185 -202 ± 3 Canes Venatici I ~ 31 GSJ© 2018 www.globalscientificjournal.com GSJ: VOLUME 6, ISSUE 3, MARCH 2018 102 Andromeda III -351 ± 9 Andromeda II -188 ± 3 Triangulum Galaxy -179 ± 3 Messier 110 -241 ± 3 NGC 147 (2.53 ± 0.11 Mly) -193 ± 3 Small Magellanic Cloud 0.000527 Large Magellanic Cloud - - M32 -200 ± 6 NGC 205 -241 ± 3 IC 1613 -234 ± 1 Carina Dwarf 230 ± 60 Sextans Dwarf 224 ± 2 Ursa Minor Dwarf (200 ± 30 kly) -247 ± 1 Draco Dwarf -292 ± 21 Cassiopeia Dwarf -307 ± 2 Ursa Major II Dwarf - 116 Leo IV 130 Leo V ( 585 kly) 173 Leo T -60 Bootes II -120 Pegasus Dwarf -183 ± 0 Sculptor Dwarf 110 ± 1 Etc. -
Overview on Spectral Line Source Finding and Visualisation
CSIRO PUBLISHING Publications of the Astronomical Society of Australia, 2012, 29, 359–370 http://dx.doi.org/10.1071/AS12030 Overview on Spectral Line Source Finding and Visualisation B. S. Koribalski CSIRO Astronomy & Space Science, Australia Telescope National Facility, PO Box 76, Epping, NSW 1710, Australia Email: [email protected] Abstract: Here I will outline successes and challenges for finding spectral line sources in large data cubes that are dominated by noise. This is a 3D challenge as the sources we wish to catalog are spread over several spatial pixels and spectral channels. While 2D searches can be applied, e.g. channel by channel, optimal searches take into account the 3-dimensional nature of the sources. In this overview I will focus on HI 21-cm spectral line source detection in extragalactic surveys, in particular HIPASS, the HI Parkes All-Sky Survey and WALLABY, the ASKAP HI All-Sky Survey. I use the original HIPASS data to highlight the diversity of spectral signatures of galaxies and gaseous clouds, both in emission and absorption. Among others, I report the À1 discovery of a 680 km s wide HI absorption trough in the megamaser galaxy NGC 5793. Issues such as source confusion and baseline ripples, typically encountered in single-dish HI surveys, are much reduced in interferometric HI surveys. Several large HI emission and absorption surveys are planned for the Australian Square Kilometre Array Pathfinder (ASKAP): here we focus on WALLABY, the 21-cm survey of the sky (d , þ308; z , 0.26) which will take about one year of observing time with ASKAP. -
Expected Intermediate-Mass Black Holes in the Virgo Cluster – II. Late-Type Galaxies
MNRAS 484, 814–831 (2019) doi:10.1093/mnras/sty3068 Advance Access publication 2018 December 21 Expected intermediate-mass black holes in the Virgo cluster – II. Late-type galaxies Alister W. Graham ,1‹ Roberto Soria2,3,4 and Benjamin L. Davis 1 1Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, VIC 3122, Australia 2College of Astronomy and Space Sciences, University of the Chinese Academy of Sciences, Beijing 100049, China Downloaded from https://academic.oup.com/mnras/article-abstract/484/1/814/5256645 by Swinburne Library user on 08 April 2019 3International Centre for Radio Astronomy Research, Curtin University, GPO Box U1987, Perth, WA 6845, Australia 4Sydney Institute for Astronomy, School of Physics A28, The University of Sydney, Sydney, NSW 2006, Australia Accepted 2018 November 2. Received 2018 October 30; in original form 2018 August 10 ABSTRACT The Chandra X-ray Observatory’s Cycle 18 Large Program titled ‘Spiral galaxies of the Virgo Cluster’ will image 52 galaxies with the ACIS-S detector. Combined with archival data for an additional 22 galaxies, this will represent the complete sample of 74 spiral galaxies in the Virgo cluster with star formation rates 0.3 M yr−1. Many of these galaxies are expected to have an active nucleus, signalling the presence of a central black hole. In preparation for this survey, we predict the central black hole masses using the latest black hole scaling relations based on the spiral arm pitch angle φ, velocity dispersion σ , and total stellar mass M∗,galaxy. 2 5 With a focus on intermediate-mass black holes (IMBHs; 10 < Mbh/M < 10 ), we highlight 3 4 NGC 4713 and NGC 4178, both with Mbh ≈ 10 –10 (an estimate that is further supported in NGC 4178 by its nuclear star cluster mass). -
ARRAKIS: Atlas of Resonance Rings As Known in The
Astronomy & Astrophysics manuscript no. arrakis˙v12 c ESO 2018 September 28, 2018 ARRAKIS: atlas of resonance rings as known in the S4G⋆,⋆⋆ S. Comer´on1,2,3, H. Salo1, E. Laurikainen1,2, J. H. Knapen4,5, R. J. Buta6, M. Herrera-Endoqui1, J. Laine1, B. W. Holwerda7, K. Sheth8, M. W. Regan9, J. L. Hinz10, J. C. Mu˜noz-Mateos11, A. Gil de Paz12, K. Men´endez-Delmestre13 , M. Seibert14, T. Mizusawa8,15, T. Kim8,11,14,16, S. Erroz-Ferrer4,5, D. A. Gadotti10, E. Athanassoula17, A. Bosma17, and L.C.Ho14,18 1 University of Oulu, Astronomy Division, Department of Physics, P.O. Box 3000, FIN-90014, Finland e-mail: [email protected] 2 Finnish Centre of Astronomy with ESO (FINCA), University of Turku, V¨ais¨al¨antie 20, FI-21500, Piikki¨o, Finland 3 Korea Astronomy and Space Science Institute, 776, Daedeokdae-ro, Yuseong-gu, Daejeon 305-348, Republic of Korea 4 Instituto de Astrof´ısica de Canarias, E-38205 La Laguna, Tenerife, Spain 5 Departamento de Astrof´ısica, Universidad de La Laguna, E-38200, La Laguna, Tenerife, Spain 6 Department of Physics and Astronomy, University of Alabama, Box 870324, Tuscaloosa, AL 35487 7 European Space Agency, ESTEC, Keplerlaan 1, 2200 AG, Noorwijk, the Netherlands 8 National Radio Astronomy Observatory/NAASC, 520 Edgemont Road, Charlottesville, VA 22903, USA 9 Space Telescope Science Institute, 3700 San Antonio Drive, Baltimore, MD 21218, USA 10 European Southern Observatory, Casilla 19001, Santiago 19, Chile 11 MMTO, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721, USA 12 Departamento de Astrof´ısica, -
190 Index of Names
Index of names Ancora Leonis 389 NGC 3664, Arp 005 Andriscus Centauri 879 IC 3290 Anemodes Ceti 85 NGC 0864 Name CMG Identification Angelica Canum Venaticorum 659 NGC 5377 Accola Leonis 367 NGC 3489 Angulatus Ursae Majoris 247 NGC 2654 Acer Leonis 411 NGC 3832 Angulosus Virginis 450 NGC 4123, Mrk 1466 Acritobrachius Camelopardalis 833 IC 0356, Arp 213 Angusticlavia Ceti 102 NGC 1032 Actenista Apodis 891 IC 4633 Anomalus Piscis 804 NGC 7603, Arp 092, Mrk 0530 Actuosus Arietis 95 NGC 0972 Ansatus Antliae 303 NGC 3084 Aculeatus Canum Venaticorum 460 NGC 4183 Antarctica Mensae 865 IC 2051 Aculeus Piscium 9 NGC 0100 Antenna Australis Corvi 437 NGC 4039, Caldwell 61, Antennae, Arp 244 Acutifolium Canum Venaticorum 650 NGC 5297 Antenna Borealis Corvi 436 NGC 4038, Caldwell 60, Antennae, Arp 244 Adelus Ursae Majoris 668 NGC 5473 Anthemodes Cassiopeiae 34 NGC 0278 Adversus Comae Berenices 484 NGC 4298 Anticampe Centauri 550 NGC 4622 Aeluropus Lyncis 231 NGC 2445, Arp 143 Antirrhopus Virginis 532 NGC 4550 Aeola Canum Venaticorum 469 NGC 4220 Anulifera Carinae 226 NGC 2381 Aequanimus Draconis 705 NGC 5905 Anulus Grahamianus Volantis 955 ESO 034-IG011, AM0644-741, Graham's Ring Aequilibrata Eridani 122 NGC 1172 Aphenges Virginis 654 NGC 5334, IC 4338 Affinis Canum Venaticorum 449 NGC 4111 Apostrophus Fornac 159 NGC 1406 Agiton Aquarii 812 NGC 7721 Aquilops Gruis 911 IC 5267 Aglaea Comae Berenices 489 NGC 4314 Araneosus Camelopardalis 223 NGC 2336 Agrius Virginis 975 MCG -01-30-033, Arp 248, Wild's Triplet Aratrum Leonis 323 NGC 3239, Arp 263 Ahenea -
Making a Sky Atlas
Appendix A Making a Sky Atlas Although a number of very advanced sky atlases are now available in print, none is likely to be ideal for any given task. Published atlases will probably have too few or too many guide stars, too few or too many deep-sky objects plotted in them, wrong- size charts, etc. I found that with MegaStar I could design and make, specifically for my survey, a “just right” personalized atlas. My atlas consists of 108 charts, each about twenty square degrees in size, with guide stars down to magnitude 8.9. I used only the northernmost 78 charts, since I observed the sky only down to –35°. On the charts I plotted only the objects I wanted to observe. In addition I made enlargements of small, overcrowded areas (“quad charts”) as well as separate large-scale charts for the Virgo Galaxy Cluster, the latter with guide stars down to magnitude 11.4. I put the charts in plastic sheet protectors in a three-ring binder, taking them out and plac- ing them on my telescope mount’s clipboard as needed. To find an object I would use the 35 mm finder (except in the Virgo Cluster, where I used the 60 mm as the finder) to point the ensemble of telescopes at the indicated spot among the guide stars. If the object was not seen in the 35 mm, as it usually was not, I would then look in the larger telescopes. If the object was not immediately visible even in the primary telescope – a not uncommon occur- rence due to inexact initial pointing – I would then scan around for it. -
Ngc Catalogue Ngc Catalogue
NGC CATALOGUE NGC CATALOGUE 1 NGC CATALOGUE Object # Common Name Type Constellation Magnitude RA Dec NGC 1 - Galaxy Pegasus 12.9 00:07:16 27:42:32 NGC 2 - Galaxy Pegasus 14.2 00:07:17 27:40:43 NGC 3 - Galaxy Pisces 13.3 00:07:17 08:18:05 NGC 4 - Galaxy Pisces 15.8 00:07:24 08:22:26 NGC 5 - Galaxy Andromeda 13.3 00:07:49 35:21:46 NGC 6 NGC 20 Galaxy Andromeda 13.1 00:09:33 33:18:32 NGC 7 - Galaxy Sculptor 13.9 00:08:21 -29:54:59 NGC 8 - Double Star Pegasus - 00:08:45 23:50:19 NGC 9 - Galaxy Pegasus 13.5 00:08:54 23:49:04 NGC 10 - Galaxy Sculptor 12.5 00:08:34 -33:51:28 NGC 11 - Galaxy Andromeda 13.7 00:08:42 37:26:53 NGC 12 - Galaxy Pisces 13.1 00:08:45 04:36:44 NGC 13 - Galaxy Andromeda 13.2 00:08:48 33:25:59 NGC 14 - Galaxy Pegasus 12.1 00:08:46 15:48:57 NGC 15 - Galaxy Pegasus 13.8 00:09:02 21:37:30 NGC 16 - Galaxy Pegasus 12.0 00:09:04 27:43:48 NGC 17 NGC 34 Galaxy Cetus 14.4 00:11:07 -12:06:28 NGC 18 - Double Star Pegasus - 00:09:23 27:43:56 NGC 19 - Galaxy Andromeda 13.3 00:10:41 32:58:58 NGC 20 See NGC 6 Galaxy Andromeda 13.1 00:09:33 33:18:32 NGC 21 NGC 29 Galaxy Andromeda 12.7 00:10:47 33:21:07 NGC 22 - Galaxy Pegasus 13.6 00:09:48 27:49:58 NGC 23 - Galaxy Pegasus 12.0 00:09:53 25:55:26 NGC 24 - Galaxy Sculptor 11.6 00:09:56 -24:57:52 NGC 25 - Galaxy Phoenix 13.0 00:09:59 -57:01:13 NGC 26 - Galaxy Pegasus 12.9 00:10:26 25:49:56 NGC 27 - Galaxy Andromeda 13.5 00:10:33 28:59:49 NGC 28 - Galaxy Phoenix 13.8 00:10:25 -56:59:20 NGC 29 See NGC 21 Galaxy Andromeda 12.7 00:10:47 33:21:07 NGC 30 - Double Star Pegasus - 00:10:51 21:58:39 -
Arxiv:2001.03626V1 [Astro-Ph.GA] 10 Jan 2020 Max Planck Institute for Astronomy K¨Onigstuhl17, 69121 Heidelberg, Germany E-Mail: [email protected] A
The Astronomy and Astrophysics Review (2020) Nuclear star clusters Nadine Neumayer · Anil Seth · Torsten B¨oker Received: date / Accepted: date Abstract We review the current knowledge about nuclear star clusters (NSCs), the spectacularly dense and massive assemblies of stars found at the centers of most galaxies. Recent observational and theoretical work suggest that many NSC properties, including their masses, densities, and stellar populations vary with the properties of their host galaxies. Understanding the formation, growth, and ultimate fate of NSCs therefore is crucial for a complete picture of galaxy evolution. Throughout the review, we attempt to combine and distill the available evidence into a coherent picture of NSC 9 evolution. Combined, this evidence points to a clear transition mass in galaxies of 10 M where the characteristics of nuclear star clusters change. We argue that at lower masses, NSCs∼ are formed primarily from globular clusters that inspiral into the center of the galaxy, while at higher masses, star formation within the nucleus forms the bulk of the NSC. We also discuss the coexistence of NSCs and central black holes, and how their growth may be linked. The extreme densities of NSCs and their interaction with massive black holes lead to a wide range of unique phenomena including tidal disruption and gravitational wave events. Lastly, we review the evidence that many NSCs end up in the halos of massive galaxies stripped of the stars that surrounded them, thus providing valuable tracers of the galaxies' accretion histories. Contents 1 Introduction . .2 2 Early studies . .4 2.1 Imaging nuclear star clusters: the Hubble Space Telescope . -
Molecular Gas in Virgo Cluster Spiral Galaxies
University of Massachusetts Amherst ScholarWorks@UMass Amherst Doctoral Dissertations 1896 - February 2014 1-1-1987 Molecular gas in Virgo Cluster spiral galaxies. Jeffrey D. Kenney University of Massachusetts Amherst Follow this and additional works at: https://scholarworks.umass.edu/dissertations_1 Recommended Citation Kenney, Jeffrey D., "Molecular gas in Virgo Cluster spiral galaxies." (1987). Doctoral Dissertations 1896 - February 2014. 1756. https://scholarworks.umass.edu/dissertations_1/1756 This Open Access Dissertation is brought to you for free and open access by ScholarWorks@UMass Amherst. It has been accepted for inclusion in Doctoral Dissertations 1896 - February 2014 by an authorized administrator of ScholarWorks@UMass Amherst. For more information, please contact [email protected]. MOLECULAR GAS IN VIRGO CLUSTER SPIRAL GALAXIES A Dissertation Presented by Jeffrey D. Kenney Submitted to the Graduate School of the University of Massachusetts in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY May 1987 Department of Physics and Astronomy Copyright ® 1987 by Jeffrey D. Kenney All rights reserved ii Molecular Gas in Virgo Cluster Spiral Galaxies A. Dissertation Presented by Jeffrey D. Kenney Approved as to style and content by; Ji^dith S. Young, Ciiairpe^son William A. Dent, Member . Peter Schloerb, Member Stevan7^ E. Strom, Member Robert V. Krotkov, Outside Member Martha P. Hay ne^, Outs ide Member Robert Hal lock, Department Head Department of Physics and Astronomy 111 ACKNOWLEDGEMENTS