Isolated Ellipticals and Their Globular Cluster Systems III. NGC 2271, NGC
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Lateinischer Name: Deutscher Name: Hya Hydra Wasserschlange
Lateinischer Name: Deutscher Name: Hya Hydra Wasserschlange Atlas Karte (2000.0) Kulmination um Cambridge 10, 16, Mitternacht: Star Atlas 17 12, 13, Sky Atlas Benachbarte Sternbilder: 20, 21 Ant Cnc Cen Crv Crt Leo Lib 9. Februar Lup Mon Pup Pyx Sex Vir Deklinationsbereic h: -35° ... 7° Fläche am Himmel: 1303° 2 Mythologie und Geschichte: Bei der nördlichen Wasserschlange überlagern sich zwei verschiedene Bilder aus der griechischen Mythologie. Das erste Bild zeugt von der eher harmlosen Wasserschlange aus der Geschichte des Raben : Der Rabe wurde von Apollon ausgesandt, um mit einem goldenen Becher frisches Quellwasser zu holen. Stattdessen tat sich dieser an Feigen gütlich und trug bei seiner Rückkehr die Wasserschlange in seinen Fängen, als angebliche Begründung für seine Verspätung. Um jedermann an diese Untat zu erinnern, wurden der Rabe samt Becher und Wasserschlange am Himmel zur Schau gestellt. Von einem ganz anderen Schlag war die Wasserschlange, mit der Herakles zu tun hatte: In einem Sumpf in der Nähe von Lerna, einem See und einer Stadt an der Küste von Argo, hauste ein unsagbar gefährliches und grässliches Untier. Diese Schlange soll mehrere Köpfe gehabt haben. Fünf sollen es gewesen sein, aber manche sprechen auch von sechs, neun, ja fünfzig oder hundert Köpfen, aber in jedem Falle war der Kopf in der Mitte unverwundbar. Fürchterlich war es, da diesen grässlichen Mäulern - ob die Schlange nun schlief oder wachte - ein fauliger Atem, ein Hauch entwich, dessen Gift tödlich war. Kaum schlug ein todesmutiger Mann dem Untier einen Kopf ab, wuchsen auf der Stelle zwei neue Häupter hervor, die noch furchterregender waren. Eurystheus, der König von Argos, beauftragte Herakles in seiner zweiten Aufgabe diese lernäische Wasserschlange zu töten. -
Extending the M (Bh)-Sigma Diagram with Dense Nuclear Star Clusters
Mon. Not. R. Astron. Soc. 000, 000–000 (0000) Printed 11 November 2018 (MN LATEX style file v2.2) Extending the Mbh–σ diagram with dense nuclear star clusters Alister W. Graham1⋆, 1 Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia. Submitted 08 Aug, 2011 ABSTRACT Four new nuclear star cluster masses, Mnc, plus seven upper limits, are provided for galaxies with previously determined black hole masses, Mbh. Together with a sample of 64 galaxies with direct Mbh measurements, 13 of which additionally now have Mnc measurements rather than only upper limits, plus an additional 29 dwarf galaxies with available Mnc measurements and velocity dispersions σ, an (Mbh + Mnc)–σ diagram is constructed. Given that major dry galaxy merger events preserve the Mbh/L ratio, and given that L ∝ σ5 for luminous galaxies, it is first noted that the observation 5 Mbh ∝ σ is consistent with expectations. For the fainter elliptical galaxies it is known 2 that L ∝ σ , and assuming a constant Mnc/L ratio (Ferrarese et al.), the expectation 2 that Mnc ∝ σ is in broad agreement with our new observational result that Mnc ∝ σ1.57±0.24. This exponent is however in contrast to the value of ∼4 which has been reported previously and interpreted in terms of a regulating feedback mechanism from stellar winds. Finally, it is predicted that host galaxies fainter than MB ∼−20.5 mag (i.e. those 5 not formed in dry merger events) which follow the relation Mbh ∝ σ , and are thus not ‘pseudobulges’, should not have a constant Mbh/Mhost ratio but instead have ∝ 5/2 Mbh Lhost. -
SUPERMASSIVE BLACK HOLES and THEIR HOST SPHEROIDS III. the MBH − Nsph CORRELATION
The Astrophysical Journal, 821:88 (8pp), 2016 April 20 doi:10.3847/0004-637X/821/2/88 © 2016. The American Astronomical Society. All rights reserved. SUPERMASSIVE BLACK HOLES AND THEIR HOST SPHEROIDS. III. THE MBH–nsph CORRELATION Giulia A. D. Savorgnan Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia; [email protected] Received 2015 December 6; accepted 2016 March 6; published 2016 April 13 ABSTRACT The Sérsic R1 n model is the best approximation known to date for describing the light distribution of stellar spheroidal and disk components, with the Sérsic index n providing a direct measure of the central radial concentration of stars. The Sérsic index of a galaxy’s spheroidal component, nsph, has been shown to tightly correlate with the mass of the central supermassive black hole, MBH.TheMnBH– sph correlation is also expected from other two well known scaling relations involving the spheroid luminosity, Lsph:theLsph–n sph and the MLBH– sph. Obtaining an accurate estimate of the spheroid Sérsic index requires a careful modeling of a galaxy’s light distribution and some studies have failed to recover a statistically significant MnBH– sph correlation. With the aim of re-investigating the MnBH– sph and other black hole mass scaling relations, we performed a detailed (i.e., bulge, disks, bars, spiral arms, rings, halo, nucleus, etc.) decomposition of 66 galaxies, with directly measured black hole masses, that had been imaged at 3.6 μm with Spitzer.Inthispaper,the third of this series, we present an analysis of the Lsph–n sph and MnBH– sph diagrams. -
Scaling Mass Profiles Around Elliptical Galaxies Observed with Chandra
Scaling Mass Profiles around Elliptical Galaxies Observed with Chandra and XMM-Newton Y. Fukazawa1, J. G. Betoya-Nonesa1, J. Pu1, A. Ohto1, and N. Kawano1 Department of Physical Science, School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526 [email protected] ABSTRACT We investigated the dynamical structure of 53 elliptical galaxies, based on the Chandra archival X-ray data. In X-ray luminous galaxies, a temperature increases with radius and a gas density is systematically higher at the optical outskirts, indicating a presence of a significant amount of the group-scale hot gas. In contrast, X-ray dim galaxies show a flat or declining temperature profile against radius and the gas density is relatively lower at the optical outskirts. Thus it is found that X-ray bright and faint elliptical galaxies are clearly distinguished by the temperature and gas density profile. The mass profile is well scaled by a virial radius r200 rather than an optical-half radius re, and is quite similar at (0.001 − 0.03)r200 between X-ray luminous and dim galaxies, and smoothly connects to those of clusters of galaxies. At the inner region of (0.001 − 0.01)r200 or (0.1 − 1)re, the mass profile well traces a stellar mass with a constant mass-to- light ratio of M/LB =3 − 10(M⊙/L⊙). M/LB ratio of X-ray bright galaxies rises up steeply beyond 0.01r200, and thus requires a presence of massive dark matter halo. From the deprojection analysis combined with the XMM-Newton data, we arXiv:astro-ph/0509521v1 18 Sep 2005 found that X-ray dim galaxies, NGC 3923, NGC 720, and IC 1459, also have a high M/LB ratio of 20–30 at 20 kpc, comparable to that of X-ray luminous galaxies. -
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. -
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. -
Star Formation in Low Density HI Gas Around the Elliptical Galaxy NGC 2865 F
A&A 606, A77 (2017) Astronomy DOI: 10.1051/0004-6361/201731032 & c ESO 2017 Astrophysics Star formation in low density HI gas around the elliptical galaxy NGC 2865 F. Urrutia-Viscarra1; 2, S. Torres-Flores1, C. Mendes de Oliveira3, E. R. Carrasco2, D. de Mello4, and M. Arnaboldi5; 6 1 Departamento de Física y Astronomía, Universidad de La Serena, Av. Cisternas 1200 Norte, La Serena, Chile e-mail: [email protected]; [email protected] 2 Gemini Observatory/AURA, Southern Operations Center, Casilla 603 La Serena, Chile 3 Departamento de Astronomia, Instituto de Astronomia, Geofísica e Ciências Atmosféricas da USP, Rua do Matão 1226, Cidade Universitária, 05508-090 São Paulo, Brazil 4 Observational Cosmology Laboratory, Code 665, Goddard Space Flight Center, Greenbelt, MD 20771, USA 5 European Southern Observatory, Karl-Schwarzschild-Strasse 2, 85748 Garching, Germany 6 INAF, Observatory of Pino Torinese, 10025 Turin, Italy Received 24 April 2017 / Accepted 19 June 2017 ABSTRACT Context. Interacting galaxies surrounded by Hi tidal debris are ideal sites for the study of young clusters and tidal galaxy formation. The process that triggers star formation in the low-density environments outside galaxies is still an open question. New clusters and galaxies of tidal origin are expected to have high metallicities for their luminosities. Spectroscopy of such objects is, however, at the limit of what can be done with existing 8−10 m class telescopes, which has prevented statistical studies of these objects. Aims. NGC 2865 is a UV-bright merging elliptical galaxy with shells and extended Hi tails. In this work we aim to observe regions previously detected using multi-slit imaging spectroscopy. -
The Black Hole Mass–Bulge Mass Correlation: Bulges Versus Pseudo-Bulges
Mon. Not. R. Astron. Soc. 000, 1–22 (2009) Printed 18 July 2021 (MN LATEX style file v2.2) The black hole mass–bulge mass correlation: bulges versus pseudo-bulges Jian Hu? Max-Planck-Institut fur¨ Astrophysik, Karl-Schwarzschild-Straße 1, D-85741 Garching bei Munchen,¨ Germany Accepted 2009 ... Received 2009 ...; in original form 2009 ... ABSTRACT We investigate the scaling relations between the supermassive black holes (SMBHs) mass (Mbh) and the host bulge mass in elliptical galaxies, classical bulges, and pseudo-bulges. We use two-dimensional image analysis software BUDDA to obtain the structural parameters of 57 galaxies with dynamical Mbh measurement, and determine the bulge K-band luminosi- ties (Lbul,K), stellar masses (Ms), and dynamical masses (Md). The updated Mbh-Lbul,K, Mbh- Ms, and Mbh-Md correlations for elliptical galaxies and classical bulges give Mbh'0.006Ms 11 or 0.003Md. The most tight relationship is log(Mbh/M ) = α + β log(Md=10 M ), with α = 8:46 ± 0:05, β = 0:90 ± 0:06, and intrinsic scatter 0 = 0:27 dex. The pseudo-bulges follow their own relations, they harbor an order of magnitude smaller black holes than those in the same massive classical bulges, i.e. Mbh'0.0003Ms or 0.0002Md. Besides the Mbh-σ∗ (bulge stellar velocity dispersion) relation, these bulge type dependent Mbh-Mbul scaling rela- tions provide information for the growth and coevolution histories of SMBHs and their host bulges. We also find the core elliptical galaxies obey the same Mbh-Md relation with other normal elliptical galaxies, that is expected in the dissipationless merger scenario. -
May 2016 BRAS Newsletter
May 2016 Issue th Next Meeting: Monday, May 9 at 7PM at HRPO (2nd Mondays, Highland Road Park Observatory) What's In This Issue? President’s Message Secretary's Summary of April Meeting Outreach Report Past Events Summary with Photos of” Rockin’ At The Swamp, Zippety Zoo Fest, Louisiana Earth Day Recent BRAS Forum Entries 20/20 Vision Campaign Geaux Green Committee Meeting Report Message from the HRPO International Astronomy Day Observing Notes: Hydra, the Water Snake, by John Nagle Newsletter of the Baton Rouge Astronomical Society May 2016 President’s Message We had a busy month with outreaches last month, and we have some major outreaches this month: The Transit of Mercury on Monday May 9th, from 6AM to 2PM at HRPO; International Astronomy Day (the 10th consecutive for us) on Saturday May 14th, 3PM to 11PM at HRPO; and Mars Closest Approach (to Earth) on Monday May 30th, 8PM to 12AM at HRPO. Volunteers are welcome. There was a good turnout at the April BRAS meeting with Dr. Giaime, Observatory Head of LIGO Livingston, as our guest speaker. His talk was very informative about the history of the search for gravity waves, Einstein’s theory on gravity waves, and what gravity waves are. The May BRAS meeting’s guest speaker will be Chris Johnson, of the LSU Astronomy Department, giving a presentation titled “Variability of Optical Counterparts to Selected X-ray Sources in the Galactic Bulge”. This is part of his Ph.D. research and has something to do with variable stars and what we can learn from space and ground based telescopes. -
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:1906.04212V2 [Astro-Ph.GA] 27 Jun 2019
Ultra light Thomas-Fermi Dark Matter K. Pal,∗ L. V. Sales,y and J. Wudkaz Department of Physics and Astronomy, UC Riverside, Riverside, CA 92521-0413, U.S.A We investigate the viability of a simple dark matter (DM) model consisting of a single fermion in the context of galactic dynamics. We use a consistent approach that does not presume a particular DM density profile but instead requires that the DM+baryon system is in hydrostatic equilibrium. Using a phenomenological baryon density profile, the model then predicts the DM distribution with a core like behavior close to the galactic center. The presence of supermassive black holes (SMBHs) in the center of large galaxies arises naturally in this framework. Using data from a set of large elliptical and spiral galaxies, and from a small set of dwarf galaxies, we find that the model can explain most of the bulk galactic properties, as well as some of the features observed in the rotation curves, provided the DM mass is in the O(50 eV) range. More precise tests of the model require better modeling of the baryon profile and better control on the uncertainties in the data. arXiv:1906.04212v2 [astro-ph.GA] 27 Jun 2019 ∗ [email protected] y [email protected] z [email protected] 2 I. INTRODUCTION The nature of dark matter (DM) remains one of the most pressing questions in modern cosmology and astrophysics; despite enormous theoretical and observational/experimental efforts, no definite DM candidate, or even paradigm for the dark sector, has been generally accepted.