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Astronomy Magazine Special Issue
γ ι ζ γ δ α κ β κ ε γ β ρ ε ζ υ α φ ψ ω χ α π χ φ γ ω ο ι δ κ α ξ υ λ τ μ β α σ θ ε β σ δ γ ψ λ ω σ η ν θ Aι must-have for all stargazers η δ μ NEW EDITION! ζ λ β ε η κ NGC 6664 NGC 6539 ε τ μ NGC 6712 α υ δ ζ M26 ν NGC 6649 ψ Struve 2325 ζ ξ ATLAS χ α NGC 6604 ξ ο ν ν SCUTUM M16 of the γ SERP β NGC 6605 γ V450 ξ η υ η NGC 6645 M17 φ θ M18 ζ ρ ρ1 π Barnard 92 ο χ σ M25 M24 STARS M23 ν β κ All-in-one introduction ALL NEW MAPS WITH: to the night sky 42,000 more stars (87,000 plotted down to magnitude 8.5) AND 150+ more deep-sky objects (more than 1,200 total) The Eagle Nebula (M16) combines a dark nebula and a star cluster. In 100+ this intense region of star formation, “pillars” form at the boundaries spectacular between hot and cold gas. You’ll find this object on Map 14, a celestial portion of which lies above. photos PLUS: How to observe star clusters, nebulae, and galaxies AS2-CV0610.indd 1 6/10/10 4:17 PM NEW EDITION! AtlAs Tour the night sky of the The staff of Astronomy magazine decided to This atlas presents produce its first star atlas in 2006. -
The Antennae Galaxies Move Closer 9 May 2008
The Antennae Galaxies move closer 9 May 2008 archetypal merging galaxy system and are used as a standard against which to validate theories about galaxy evolution. An international group of scientists led by Ivo Saviane from the European Southern Observatory has used Hubble’s Advanced Camera for Surveys and Wide Field Planetary Camera 2 to observe individual stars spawned by the colossal cosmic collision in the Antennae Galaxies. They reached an interesting and surprising conclusion. By measuring the colours and brightnesses of red giant stars in the system, the scientists found that The Antennae Galaxies are among the closest known the Antennae Galaxies are much closer than merging galaxies. The two galaxies, also known as NGC previously thought: 45 million light-years instead of 4038 and NGC 4039, started to interact a few hundred the previous best estimate of 65 million light-years. million years ago, creating one of the most impressive sights in the night sky. They are considered by scientists as the archetypal merging galaxy system and are used The team targeted a region in the relatively as a standard with which to validate theories about quiescent outer regions in the southern tidal tail, galaxy evolution. The ground-based image (left) is taken away from the active central regions. This tail by Robert Gendler and shows the two merging galaxies consists of material thrown from the main galaxies and their impressive long tidal tails. The Hubble as they collided. The scientists needed to observe Advanced Camera for Surveys image (right) shows a regions with older red giant stars to derive an portion of the southern tidal tail. -
333 — 15 September 2020 Editor: Bo Reipurth ([email protected]) List of Contents
THE STAR FORMATION NEWSLETTER An electronic publication dedicated to early stellar/planetary evolution and molecular clouds No. 333 — 15 September 2020 Editor: Bo Reipurth ([email protected]) List of Contents The Star Formation Newsletter Editorial ....................................... 3 Interview ...................................... 4 Editor: Bo Reipurth [email protected] My Favorite Object ............................ 7 Associate Editor: Anna McLeod Perspective ................................... 14 [email protected] Abstracts of Newly Accepted Papers .......... 18 Technical Editor: Hsi-Wei Yen Abstracts of Newly Accepted Major Reviews .. 51 [email protected] Dissertation Abstracts ........................ 52 Editorial Board New Jobs ..................................... 56 Short Announcements ........................ 58 Joao Alves Alan Boss Meetings ..................................... 59 Jerome Bouvier Summary of Upcoming Meetings .............. 60 Lee Hartmann Thomas Henning New Books ................................... 61 Paul Ho Passings ...................................... 63 Jes Jorgensen Charles J. Lada Thijs Kouwenhoven Michael R. Meyer Ralph Pudritz Luis Felipe Rodríguez Cover Picture Ewine van Dishoeck Hans Zinnecker The image shows the active star forming regions of M8 and M20 and associated giant molecular clouds, The Star Formation Newsletter is a vehicle for together with the hidden Galactic Center to the fast distribution of information of interest for as- lower left. The small Bok globule Barnard 86 is tronomers working on star and planet formation seen near the center of the image against the rich and molecular clouds. You can submit material star fields of Sagittarius. The vertical axis is 10◦, for the following sections: Abstracts of recently with north up and east left. accepted papers (only for papers sent to refereed journals), Abstracts of recently accepted major re- Image by Bo Reipurth (Canon EOS Ra, 30 sec, views (not standard conference contributions), Dis- 135mm lens at f/2, ISO 6400). -
A Search For" Dwarf" Seyfert Nuclei. VII. a Catalog of Central Stellar
TO APPEAR IN The Astrophysical Journal Supplement Series. Preprint typeset using LATEX style emulateapj v. 26/01/00 A SEARCH FOR “DWARF” SEYFERT NUCLEI. VII. A CATALOG OF CENTRAL STELLAR VELOCITY DISPERSIONS OF NEARBY GALAXIES LUIS C. HO The Observatories of the Carnegie Institution of Washington, 813 Santa Barbara St., Pasadena, CA 91101 JENNY E. GREENE1 Department of Astrophysical Sciences, Princeton University, Princeton, NJ ALEXEI V. FILIPPENKO Department of Astronomy, University of California, Berkeley, CA 94720-3411 AND WALLACE L. W. SARGENT Palomar Observatory, California Institute of Technology, MS 105-24, Pasadena, CA 91125 To appear in The Astrophysical Journal Supplement Series. ABSTRACT We present new central stellar velocity dispersion measurements for 428 galaxies in the Palomar spectroscopic survey of bright, northern galaxies. Of these, 142 have no previously published measurements, most being rela- −1 tively late-type systems with low velocity dispersions (∼<100kms ). We provide updates to a number of literature dispersions with large uncertainties. Our measurements are based on a direct pixel-fitting technique that can ac- commodate composite stellar populations by calculating an optimal linear combination of input stellar templates. The original Palomar survey data were taken under conditions that are not ideally suited for deriving stellar veloc- ity dispersions for galaxies with a wide range of Hubble types. We describe an effective strategy to circumvent this complication and demonstrate that we can still obtain reliable velocity dispersions for this sample of well-studied nearby galaxies. Subject headings: galaxies: active — galaxies: kinematics and dynamics — galaxies: nuclei — galaxies: Seyfert — galaxies: starburst — surveys 1. INTRODUCTION tors, apertures, observing strategies, and analysis techniques. -
April 14 2018 7:00Pm at the April 2018 Herrett Center for Arts & Science College of Southern Idaho
Snake River Skies The Newsletter of the Magic Valley Astronomical Society www.mvastro.org Membership Meeting President’s Message Tim Frazier Saturday, April 14th 2018 April 2018 7:00pm at the Herrett Center for Arts & Science College of Southern Idaho. It really is beginning to feel like spring. The weather is more moderate and there will be, hopefully, clearer skies. (I write this with some trepidation as I don’t want to jinx Public Star Party Follows at the it in a manner similar to buying new equipment will ensure at least two weeks of Centennial Observatory cloudy weather.) Along with the season comes some great spring viewing. Leo is high overhead in the early evening with its compliment of galaxies as is Coma Club Officers Berenices and Virgo with that dense cluster of extragalactic objects. Tim Frazier, President One of my first forays into the Coma-Virgo cluster was in the early 1960’s with my [email protected] new 4 ¼ inch f/10 reflector and my first star chart, the epoch 1960 version of Norton’s Star Atlas. I figured from the maps I couldn’t miss seeing something since Robert Mayer, Vice President there were so many so closely packed. That became the real problem as they all [email protected] appeared as fuzzy spots and the maps were not detailed enough to distinguish one galaxy from another. I still have that atlas as it was a precious Christmas gift from Gary Leavitt, Secretary my grandparents but now I use better maps, larger scopes and GOTO to make sure [email protected] it is M84 or M86. -
Star Formation
IV. Star Formation 1. Basic Aspects of Star Formation • Star Formation: The fundamental cosmic (baryonic) process Determines cosmic fate of normal matter Galaxy formation, Star Conditions for life evolution, IMF Formation Elements Planet formation (He => U) Clusters Light, K.E. of ISM black holes WS 2018/19 (AGN,CDE stellar) IV 2 1 Star formation visible on local scales 3 Stellar associations: Does the energy feedback self-regulate the SF? 2. Star Formation in Spiral Galaxies IC5333 in Hα star formation follows the gaseous spiral arms. 4 2 Star formation can also happen in diffuse, less dense HI gas at the rim of gas disks. NGC 4625 UV disk is 4x larger than optical disk. Gil de Paz et al. (2005) 6 3 2.1. “Kennicutt/Schmidt law”: 2 global relat.s n SF threshold at g 6 M SF g (1989) ApJ, ˙ n 1.4 WS 2018/19 CDE IV 8 4 1.40.15 (2.5 0.7) 104 g M yr 1kpc 2 SF 2 s 1Ms pc g SF 0.017 g g dyn WS 2018/19 CDE IV 9 Kennicutt (1998) ApJ, 498 Can we understand the SF – gas surface density relation? if large - scale SF is produced by small - scale dynamics over a large area : g g 1.5 (for const. H) SF 1 g SF 2 (G g ) but : SF could be very short WS 2018/19 CDE IV 10 5 Starbursting galaxies drop off the KS correlation; the same for mergers. Hensler (2012) ApSS Proceed. + WS 2018/19 CDE IV Kuehtreiber (2010) BSc. -
X-Ray Luminosities for a Magnitude-Limited Sample of Early-Type Galaxies from the ROSAT All-Sky Survey
Mon. Not. R. Astron. Soc. 302, 209±221 (1999) X-ray luminosities for a magnitude-limited sample of early-type galaxies from the ROSAT All-Sky Survey J. Beuing,1* S. DoÈbereiner,2 H. BoÈhringer2 and R. Bender1 1UniversitaÈts-Sternwarte MuÈnchen, Scheinerstrasse 1, D-81679 MuÈnchen, Germany 2Max-Planck-Institut fuÈr Extraterrestrische Physik, D-85740 Garching bei MuÈnchen, Germany Accepted 1998 August 3. Received 1998 June 1; in original form 1997 December 30 Downloaded from https://academic.oup.com/mnras/article/302/2/209/968033 by guest on 30 September 2021 ABSTRACT For a magnitude-limited optical sample (BT # 13:5 mag) of early-type galaxies, we have derived X-ray luminosities from the ROSATAll-Sky Survey. The results are 101 detections and 192 useful upper limits in the range from 1036 to 1044 erg s1. For most of the galaxies no X-ray data have been available until now. On the basis of this sample with its full sky coverage, we ®nd no galaxy with an unusually low ¯ux from discrete emitters. Below log LB < 9:2L( the X-ray emission is compatible with being entirely due to discrete sources. Above log LB < 11:2L( no galaxy with only discrete emission is found. We further con®rm earlier ®ndings that Lx is strongly correlated with LB. Over the entire data range the slope is found to be 2:23 60:12. We also ®nd a luminosity dependence of this correlation. Below 1 log Lx 40:5 erg s it is consistent with a slope of 1, as expected from discrete emission. -
Im Fokus Hyaden in Den
DAS UMFASSENDE ASTRONOMISCHE JAHRBUCH Himmels- EXTRA 2 | 2016 EXTRA Almanach 2017 DATEN | DETAILLIERTE KARTEN | PRAXISTIPPS TOP-EREIGNISSE 2017 NGC 4513 UGCA 272 UGC 5336 M 81 Arp 300 ρ UGC 4539 64° Bode's Galaxy 64° Holmberg IX NGC 2959 Σ UGC 5028 RV NGC 4108 R 1400 NGC 2961 5 Σ 1573 NGC 3077 5 NGC 4256 NGC 4221 IC 2574 The Garland σ 2 Σ 1349 σ NGC 4332 Coddington's Nebula FBS 0959+685 NGC 2892 1 NGC 4210 Σ 1306 DERNGC 4441 WEGWEISERNGC 3622 NGC 2976 2 63° 3 UGC 4775 63° DRA NGC 4391 Sh 86 π 1 NGC 4125 VY NGC 4521 HCG 49 NGC 4545 NGC 3682 NGC 4510 NGC 4121 Σ 1350 FÜR DAS GESAMTE JAHR π 2 62° NGC 3231 62° 76 6 NGC 4205 ASTRONOMISCHE EREIGNISSE 57 UGC 5188 NGC 4081 NGC 3392 UGC 4159 UGC 7179 38 WOCHE FÜR WOCHE NGC 3394 35 UGC 6316 61° MCG +11-12-10 61° Σ 1559 NGC 2814 TOTALE S NGC 4605 UGC 5576 32 NGC 3259 β 408 NGC 2820 NGC 2805 τ SONNENFINSTERNIS NGC 3266 56 CGCG 292-85 60° NGC 4041 60° RY 28 5 ο BEOBACHTUNGSTIPPS UGC 6534 UGC 5776 NGC 4036 NGC 3668 23 UGC 7406 29 Muscida IN DEN USA UGC 6520 Σ 1351 MCG +11-14-33 T MCG +10-17-64 NGC 2742A MCG +10-18-51VON EXPERTEN NGC 3359 59° NGC 2880 59° NGC 3725 Σ 1315 UGC 6528 16 NGC 4547 VERSTÄNDLICHE ERKLÄRUNGEN RS NGC 3978 NGC 3762 NGC 2654 75 Shk 105 UGC 4289 NGC 3945 α FÜR EINSTEIGER ΟΣ 235 Dubhe MCG +10-12-103 74 TT 58° NGC 3835A NGC 2742 58° β 1077 UMA UGC 4730 NGC 4358 NGC 3471 NGC 4335 NGC 3835 NGC 3796 ΟΣΣ NGC 4500 Shk 124 92 NGC 2726 UGC 4549 M 40 NGC 3435 NGC 3894NGC 3809 Shk 113 NGC 4290 NGC 3895 20 NGC 2768 NGC 4149 Helix Galaxy 57° 57° 70 Arp 336 Abell 28 UGC 7635 Σ 1544 NGC 2685 UGC -
Tidal Dwarf Galaxies and Missing Baryons
Tidal Dwarf Galaxies and missing baryons Frederic Bournaud CEA Saclay, DSM/IRFU/SAP, F-91191 Gif-Sur-Yvette Cedex, France Abstract Tidal dwarf galaxies form during the interaction, collision or merger of massive spiral galaxies. They can resemble “normal” dwarf galaxies in terms of mass, size, and become dwarf satellites orbiting around their massive progenitor. They nevertheless keep some signatures from their origin, making them interesting targets for cosmological studies. In particular, they should be free from dark matter from a spheroidal halo. Flat rotation curves and high dynamical masses may then indicate the presence of an unseen component, and constrain the properties of the “missing baryons”, known to exist but not directly observed. The number of dwarf galaxies in the Universe is another cosmological problem for which it is important to ascertain if tidal dwarf galaxies formed frequently at high redshift, when the merger rate was high, and many of them survived until today. In this article, I use “dark matter” to refer to the non-baryonic matter, mostly located in large dark halos – i.e., CDM in the standard paradigm. I use “missing baryons” or “dark baryons” to refer to the baryons known to exist but hardly observed at redshift zero, and are a baryonic dark component that is additional to “dark matter”. 1. Introduction: the formation of Tidal Dwarf Galaxies A Tidal Dwarf Galaxy (TDG) is, per definition, a massive, gravitationally bound object of gas and stars, formed during a merger or distant tidal interaction between massive spiral galaxies, and is as massive as a dwarf galaxy [1] (Figure 1). -
Globular Cluster Systems of Six Shell Galaxies
A&A 458, 53–67 (2006) Astronomy DOI: 10.1051/0004-6361:20054606 & c ESO 2006 Astrophysics Globular cluster systems of six shell galaxies G. Sikkema1,R.F.Peletier1, D. Carter2, E. A. Valentijn1, and M. Balcells3 1 Kapteyn Astronomical Institute, University of Groningen, PO Box 800, 9700 AV Groningen, The Netherlands e-mail: [email protected] 2 Astrophysics Research Institute, Liverpool John Moores University, 12 Quays House, Egerton Wharf, Birkenhead, CH41 1LD, UK 3 Instituto de Astrofísica de Canarias, vía Láctea s/n, La Laguna 38200, Spain Received 29 November 2005 / Accepted 14 June 2006 ABSTRACT Context. Shells in Elliptical Galaxies are faint, sharp-edged features, believed to provide evidence of a recent (∼0.5−2 × 109 years ago) merger event. We analyse the Globular Cluster (GC) systems of six shell elliptical galaxies, to examine the effects of mergers upon the GC formation history. Aims. We examine the colour distributions, and investigate differences between red and blue globular cluster populations. We present luminosity functions, spatial distributions and specific frequencies (SN ) at 50 kpc radius for our sample. Methods. We present V and I magnitudes for cluster candidates measured with the HST Advanced Camera for Surveys (ACS). Galaxy background light is modelled and removed, and magnitudes are measured in 8 pixel (0.4 arcsec) diameter apertures. Background contamination is removed using counts from Hubble Deep Field South. Results. We find that the colour distributions for NGC 3923 and NGC 5982 have a bimodal form typical of bright ellipticals, with peaks near V − I = 0.92 ± 0.04 and V − I = 1.18 ± 0.06. -
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. -
Dynamics of Hot Gas in Galaxies, Groups, & Clusters
DynamicsDynamics ofof hothot gasgas inin Galaxies,Galaxies, Groups,Groups, && ClustersClusters Bill Mathews Colleagues: Fabrizio Brighenti (Bologna) David Buote (UC Irvine) X-ray images of groups and clusters of galaxies Conventional cooling flows Evidence that cooling flows are not cooling as expected Proposed explanations why cooling flows aren’t cooling Heating cluster gas with AGN energy by dissipation of weak shock waves by PdV work as X-ray cavities form Cosmic ray buoyancy and outward gas circulation TypicalTypical HotHot GasGas ParametersParameters E galaxies rich galaxy & groups clusters Temperature 107 108 K X-ray luminosity 1039-44 1043-46 erg/s Fe abundance 0.4-1.0 0.4 solar 12-13 14-15 Total mass 10 10 Msun Baryon fraction < 0.16 ~0.16 XMMXMM ImageImage ofof PerseusPerseus ClusterCluster X-ray contours kpc 220 200ks Chandra image is here (Churazov et al. 2003) Central active cD galaxy 14 virial mass: Mvir = 8.5x10 Msun NGC 1275 DeepDeep 200ks200ks ChandraChandra ImageImage ofof PerseusPerseus ClusterCluster X-ray cavities -- bubbles (Fabian et al. 2003) Distance 73 Mpc 45 Lx 10 erg/s kpc 22 22 Absorption from foreground gas in merging galaxy Deprojected Deprojected XMM Observationsof XMM Observationsof this region affected by AGN core emission (Churazov Perseus Perseus et al.2003) averaged azimuthally Cluster Cluster 200ks Chandra Observations in Perseus strange radial abundance gradients less accurate only Ne peaks less accurate in the core 0 r (kpc) 120 (Sanders et al. 2004) Many elements have strange off-center peaks Abundance patterns are similar in Virgo (M87) ChandraChandra andand RadioRadio ImagesImages ofof PerseusPerseus radio contours (Fabian et al.