Friday, September 25, 2009

Interesting Astrophysics: Sep 21 to Sep 25

A interesting week. Of particular note: Radio observation of young SNe/SNRs in Arp 299 (NGC 3690+IC 694) by Ulvestad and also Perez-Torres et al; empirical measures of gas consumption in galaxies by Bauermeister et al versus simulated gas accretion by Kereš et al (which makes galaxies too massive); YACRDWM (yet another cosmic ray driven wind model), this time by Samui et al; and estimates of the delay time for prompt Type Ia supernovae (Raskin et al)


Galaxies and Starbursts

Radio Emission from Young Supernovae and Supernova Remnants in Arp 299
James S. Ulvestad, arXiv:0909.3534 [ps, pdf, other]
Comments: Astronomical Journal, in press, December 2009 issue

Arp 299 = NGC 3690 + IC 694. Finds 30 point-like radio sources in the two nuclei. Also gives estimated sizes of the two regions where the young SNe/SNRs are found.

An extremely prolific supernova factory in the buried nucleus of the starburst galaxy IC 694
M.A. Perez-Torres, C. Romero-Canizales, A. Alberdi, A. Polatidis, arXiv:0909.3959 [ps, pdf, other]
Comments: Under revision by A&A, 6 pages, 2 figures

Makes a number of rather strong claims...

The Gas Consumption History to z ~ 4

Amber Bauermeister, Leo Blitz, Chung-Pei Ma, arXiv:0909.3840 [ps, pdf, other]
Comments: 10 pages, 6 figures. Submitted to ApJ

UV Continuum Slope and Dust Obscuration from z~6 to z~2: The Star Formation Rate Density at High Redshift
R.J. Bouwens, G.D. Illingworth, M. Franx, R-R. Chary, G.R. Meurer, C.J. Conselice, H. Ford, M. Giavalisco, P. van Dokkum, arXiv:0909.4074 [ps, pdf, other]
Comments: 30 pages, 15 figures, 7 tables, accepted for publication in the Astrophysical Journal

HI kinematics and dynamics of Messier 31
Laurent Chemin, Claude Carignan, Tyler Foster, arXiv:0909.3846 [ps, pdf, other]
Comments: Accepted for publication in the Astrophysical Journal, 22 pages, 17 figures. For a higher resolution version of the article, see this http URL

Low Resolution Spectral Templates For AGNs and Galaxies From 0.03 -- 30 microns
R.J. Assef, C.S. Kochanek, M. Brodwin, R. Cool, W. Forman, A.H. Gonzalez, R.C. Hickox, C. Jones, E. Le Floc'h, J. Moustakas, S.S. Murray, D. Stern, arXiv:0909.3849 [ps, pdf, other]
Comments: Submitted to The Astrophysical Journal. 23 text pages + 3 tables + 18 figures. Fortran codes, templates and electronic tables available at this http URL

Cosmic ray driven outflows from high redshift galaxies
Saumyadip Samui, Kandaswamy Subramanian, Raghunathan Srianand, arXiv:0909.3854 [pdf, other]
Comments: 14 pages, 7 figures, Submitted to MNRAS

As with all CR-driven models this relies on assuming that supernovae losing the vast majority (~90%) of their initial kinetic energy in order for the energy associated with CRs to then be significant in the remaining total. This may apply to quiescently star forming galaxies, but its a bad assumption for actively star forming galaxies.


Black Holes and AGN

Title: Characterising the Far-infrared Properties of Distant X-ray Detected AGNs: Evidence for Evolution in the Infrared--X-ray Luminosity Ratio
J. R. Mullaney, D. M. Alexander, M. Huynh, A. D. Goulding, D. Frayer, arXiv:0909.3842 [ps, pdf, other]
Comments: 20 pages, 11 figures, MNRAS accepted


Theoretical Cosmology

Galaxies in a simulated ΛCDM universe - II. Observable properties and constraints on feedback
Kereš, Dušan; Katz, Neal; Davé, Romeel; Fardal, Mark; Weinberg, David H., 2009, MNRAS, 396, 2332
Full Text: HTML, PDF (1885k)

In short they find that the over-cooling problem remains, and existing (simplistic) feedback recipes do NOT fix it.

Galaxies in a simulated ΛCDM Universe - I. Cold mode and hot cores
Kereš, Dušan; Katz, Neal; Fardal, Mark; Davé, Romeel; Weinberg, David H., 2009, MNRAS, 395, 160
Full Text: HTML, PDF (44390k)

Updated version of the older stuff on the relative strengths of cold mode and hot mode accretion onto galaxies and how accretion rates onto galaxies relate to the simulated star formation rates. NB: The end up with 3 times too many baryons in galaxies, so should we still believe that accretion is being handled correctly?

The Modelling of Feedback Processes in Cosmological Simulations of Disk Galaxy Formation
Franziska Piontek, Matthias Steinmetz, arXiv:0909.4167 [ps, pdf, other]
Comments: 21 pages, 27 figures, submitted to MNRAS


Stars, Supernovae and Planets

Discovery of Strong Radiative Recombination Continua from The Supernova Remnant IC 443 with Suzaku
Hiroya Yamaguchi, Midori Ozawa, Katsuji Koyama, Kuniaki Masai, Junko S. Hiraga, Masanobu Ozaki, Daisuke Yonetoku, arXiv:0909.3848 [ps, pdf, other]
Comments: 5 pages, 5 figures, accepted by ApJ Letter

Cosmic Origins Spectrograph Observations of the Chemical Composition of LMC N132D
Kevin France, Matthew Beasley, Brian A. Keeney, Charles W. Danforth, Cynthia S. Froning, James C. Green, arXiv:0909.4110 [ps, pdf, other]
Comments: 5 pages, 4 figures. Submitted to ApJL

Prompt Ia Supernovae Are Significantly Delayed
Cody Raskin, Evan Scannapieco, James Rhoads, Massimo Della Valle, arXiv:0909.4293 [pdf, other]
Comments: 6 pages, 6 figures, ApJ, in press

From their abstract: "Our approach confines the analysis only to the relevant portions of the hosts, allowing us to show that even so-called "prompt" SNe Ia that trace star-formation on cosmic timescales exhibit a significant delay time of 200-500 million years."

Radiation-Hydrodynamic Models of X-Ray & EUV Photoevaporating Protoplanetary Discs
J. E. Owen, B. Ercolano, C. J. Clarke, R. D. Alexander, arXiv:0909.4309 [ps, pdf, other]
Comments: 16 pages, 14 figures, accepted for publication in MNRAS

X-rays are the dominant driving mechanism for photoevaporation.

The Planetary Nebula Luminosity Function: Pieces of the Puzzle
Robin Ciardullo, arXiv:0909.4356 [ps, pdf, other]
Comments: 7 pages, including 7 figures; presentation at the workshop on the Legacies of the Macquarie/AAO/Strasbourg H-alpha Planetary Nebula project, accepted for publication in PASA

Note to self: Must read, as may have implications for understanding compact H-alpha point sources in M82 ACS data.

3D models of radiatively driven colliding winds in massive O+O star binaries - III. Thermal X-ray emission
J. M. Pittard, E. R. Parkin, arXiv:0909.4383 [ps, pdf, other]
Comments: 29 pages, 23 figures, accepted for publication in MNRAS


Other

Astroinformatics: A 21st Century Approach to Astronomy
Kirk D. Borne, arXiv:0909.3892 [pdf, other]
Comments: 14 pages total: 1 cover page, 3 pages of co-signers, plus 10 pages, Astro2010 Decadal Survey State of the Profession Position Paper

Galaxies and Cladistics
Didier Fraix-Burnet, arXiv:0909.4164 [ps, pdf, other]
Comments: Talk given at the "12th Evolutionary Biology Meeting" held in Marseille, France, Sept. 24-26, 2008
Journal-ref: Evolutionary Biology. Concept, Modeling, and Application, Pontarotti, Pierre (Ed.) (2009) 363-378

Wednesday, September 23, 2009

MacArthur Fellows for 2009 announced

This years crop of MacArthur Fellows (the so-called genius grants) has just been announced - the list of this year's Fellows is well worth a look. I like the diversity in occupation and age they cover - its not just thirty-somethings in fashionable areas.

Friday, September 18, 2009

Interesting Astrophysics: Sep 16 to Sep 18

Both ram-pressure stripping and the neutral hydrogen content of galaxies stand out as topics this week. The issue of what are the elemental abundances in the Sun continues to elude solution.


Galaxies and Starbursts

Ram pressure stripping of disk galaxies in galaxy clusters
E. Roediger, arXiv:0909.2638 [pdf, other]
Comments: 11 pages, 4 figures, to appear in proceedings of symposium "Matter Cycles of Galaxies in Clusters" at JENAM 2008 (Vienna, Sept 2008), to be published in special issue of Astronomische Nachrichten in Nov 2009. Version with full resolution figures at this http URL

Infrared Luminosities and Dust Properties of z ~ 2 Dust-Obscured Galaxies
R. S. Bussmann, Arjun Dey, C. Borys, V. Desai, B. T. Jannuzi, E. Le Floc'h, J. Melbourne, K. Sheth, B. T. Soifer, arXiv:0909.2650 [ps, pdf, other]
Comments: 16 pages, 7 figures, 6 tables; accepted to the ApJ

Setting the normalcy level of HI properties in isolated galaxies
D. Espada, L. Verdes-Montenegro, E. Athanassoula, A. Bosma, W. K. Huchtmeier, S. Leon, U. Lisenfeld, J. Sabater, J. Sulentic, S. Verley, M. Yun, arXiv:0909.2736 [ps, pdf, other]
Comments: 4 pages, 2 figures, Conference 'Galaxies in Isolation: Exploring Nature vs. Nurture', Granada, 12-15 May 2009. To be published in the ASP Conference Series

Only the Lonely: HI Imaging of Void Galaxies
K. Stanonik, E. Platen, M. A. Aragon-Calvo, J. H. van Gorkom, R. van de Weygaert, J. M. van der Hulst, K. Kovac, C.-W. Yip, P. J. E. Peebles, arXiv:0909.2869 [ps, pdf, other]
Comments: 4 pages, to be published in the proceedings of the conference "Galaxies in Isolation" (12-15 May 2009; Granada, Spain)

Low-column density HVC and IVC gas in the halo of the Milky Way
N. Ben Bekhti, P. Richter, M. T. Murphy, arXiv:0909.2797 [ps, pdf, other]
Comments: 4 pages, 2 figures, in proceedings of "Panoramic Radio Astronomy: Wide-field 1-2 GHz research on galaxy evolution - PRA2009"

Does Stellar Feedback Create HI Holes? An HST/VLA Study of Holmberg II
Daniel R. Weisz, Evan D. Skillman, John M. Cannon, Andrew E. Dolphin, Robert C. Kennicutt Jr., Jance Lee, Fabian Walter, arXiv:0909.3025 [ps, pdf, other]
Comments: Accepted for Publication in The Astrophysical Journal; 28 Pages, 31 Figures, a version of this paper with full resolution figures is available at this http URL

The Tail of the Stripped Gas that Cooled: HI, Halpha and X-ray Observational Signatures of Ram Pressure Stripping
Stephanie Tonnesen, Greg L. Bryan, arXiv:0909.3097 [ps, pdf, other]
Comments: 18 pages, 11 figures, submitted to ApJ

Dust Emissivity Variations In the Milky Way
D. Paradis, J.-Ph. Bernard, C. Meny, arXiv:0909.3236 [ps, pdf, other]
Comments: 16 pages, 6 figures, accepted in A&A


Black Holes and AGN

A strong excess in the 20-100 keV emission of NGC 1365
G. Risaliti, V. Braito, V. Laparola, S. Bianchi, M. Elvis, G. Fabbiano, R. Maiolino, G. Matt, J. Reeves, M. Salvati, J. Wang, arXiv:0909.2820 [ps, pdf, other]
Comments: 13 pages, 3 figures. Accepted for publication in ApJ Letters

XMM-Newton Observations of a Complete Sample of Optically Selected Type 2 Seyfert Galaxies
Stephanie M. LaMassa, Timothy M. Heckman, Andrew A. Ptak, Ann Hornschemeier, Lucimara Martins, Paule Sonnentrucker, Christy Tremonti, arXiv:0909.3044 [ps, pdf, other]
Comments: accepted for publication to ApJ; 48 pages, 15 figures


Stars, Supernovae and Planets

New Solar Composition: The Problem With Solar Models Revisited
Aldo Serenelli, Sarbani Basu, Jason W. Ferguson, Martin Asplund, arXiv:0909.2668 [ps, pdf, other]
Comments: 11 pages, including 3 tables and 2 figures. Submitted to ApJL

From their abstract: "We find the improved input physics in the models has minor effects on the solar model structure and we confirm that the model using high (older) metallicity determinations gives consistent results with helioseismology."


Public Understanding of Science

Galaxy Zoo: Exploring the Motivations of Citizen Science Volunteers
M. Jordan Raddick, Georgia Bracey, Pamela L. Gay, Chris J. Lintott, Phil Murray, Kevin Schawinski, Alexander S. Szalay, Jan Vandenberg, arXiv:0909.2925 [pdf, other]
Comments: 15 pages, 3 figures

Thursday, September 17, 2009

Planck first light


The BBC discusses ESA's Planck mission's first light images.