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


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.

Friday, September 11, 2009

Hubble post-servicing "first light" press release

The full list of HST post-servicing "first-light" press release images and spectra (in image form, sigh) featuring WFC3 and COS can be found at the STScI website here.

Interesting Astrophysics: Sep 07 to Sep 11

Of particular note there are interesting papers on theoretical models of dust-driven stellar winds (Mattsson et al) and SN Ia-driven galactic winds (Tang et al), along with observations of z~3 star forming galaxies showing signs of superwinds driven by core collapse supernova activity (Lemoine-Busserolle et al).

I also found Guio & Achilleos's paper on image decomposition using Voronoi tessellation quite interesting.

Galaxies and Starbursts

Cosmic-ray driven dynamo in the interstellar medium of irregular galaxies
H. Siejkowski, M. Soida, K. Otmianowska-Mazur, M. Hanasz, D.J. Bomans, arXiv:0909.0926 [ps, pdf, other]
Comments: 8 pages, 6 figures, submitted to A&A

The Distribution of Stars and Stellar Remnants at the Galactic Center
David Merritt, arXiv:0909.1318 [ps, pdf, other]
Comments: 22 pages, 18 figures

2D Kinematics and Physical Properties of z~3 Star-Forming Galaxies
M. Lemoine-Busserolle, A. Bunker, F. Lamareille, M. Kissler-Patig, arXiv:0909.1386 [pdf, other]
Comments: 14 pages and 16 figures

Their UV spectra show ISM lines blue shifted with respect to [O III]. Galactic winds! Although of course I shouldn't be surprised.

MMTF-Halpha and HST-FUV Imaging of the Filamentary Complex in Abell 1795
Michael McDonald, Sylvain Veilleux, arXiv:0909.1554 [ps, pdf, other]
Comments: Accepted for publication in ApJ Letters, 6 pages, 4 figures, 1 table

Investigating the far-IR/radio correlation of star-forming Galaxies to z= 3
N. Seymour, M. Huynh, T. Dwelly, M. Symeonidis, A. Hopkins, I. M. McHardy, M. J. Page, G. Rieke, 2009, MNRAS, 398, 1573
Full Text: HTML, PDF (Size: 751K)

Numerical Astrophysics & Hydrodynamics

Storm fronts over galaxy discs: models of how waves generate extraplanar gas and its anomalous kinematics
Curtis Struck and Daniel C. Smith, 2009, MNRAS, 398, 1069
Full Text: HTML, PDF (Size: 23343K)

The VOISE algorithm: a versatile tool for automatic segmentation of astronomical images
P. Guio and N. Achilleos, 2009, MNRAS, 398, 1254
Full Text: HTML, PDF (Size: 1354K)

Type Ia supernova-driven Galactic bulge wind
Shikui Tang, Q. Daniel Wang, Mordecai-Mark Mac Low, M. Ryan Joung, 2009, MNRAS, 398, 1468
Full Text: HTML, PDF (Size: 18550K)

The fragmentation of expanding shells – I. Limitations of the thin-shell approximation
James E. Dale, Richard Wünsch, Anthony Whitworth, Jan Palouš, 2009, MNRAS, 398, 1537
Full Text: HTML, PDF (Size: 16967K)

Stars, Supernovae and Planets

The relation between the most-massive star and its parental star cluster mass
C. Weidner, P. Kroupa, I. Bonnell, arXiv:0909.1555 [ps, pdf, other]
Comments: 26 pages, 13 figures, 3 tables, accepted for publication in MNRAS

Dust Driven Mass Loss from Carbon Stars as Function of Stellar Parameters - I. A Grid of Solar-metallicity Wind Models
Lars Mattsson, Rurik Wahlin, Susanne Hoefner, arXiv:0909.1513 [ps, pdf, other]
Comments: 27 pages, 11 figures, accepted for publication in Astronomy & Astrophysics

Wednesday, September 09, 2009

Off to Mars, but not the Moon?

The summary of the Human Space Flight Review Committee report requested by the Obama administration advocates a long-term program with Mars as the long term goal (i.e. no set date), de-emphasising any return to the Moon:

... NASA has drafted a concept proposal called "Generation Mars" which envisions a 30-year blueprint for developing technologies, staging precursor missions to asteroids and other destinations, and building grassroots support for eventual human expeditions to Mars.
It also offers an unsurprising warning:
"The U.S. human spaceflight program appears to be on an unsustainable trajectory. It is perpetuating the perilous practice of pursuing goals that do not match allocated resources," the report summary said.
[Hat tip: TPM/Reuters]

Friday, September 04, 2009

Interesting Astrophysics: Sep 01 to Sep 04

Of the 270 preprints that appeared on in the last week there were 16 that caught my eye.

Just on my favorite subject of galactic winds, Swinbank et al find evidence a galactic wind in a starburst galaxy at redshift z=4.9, Martin & Bouche present their Fe II and Mg II absorption line studies of wind in local ULIRGs, and Heesen et al present radio data on NGC 253's wind.

Galaxies and Starbursts

Probing the Excitation of Extreme Starbursts: High Resolution Mid-IR Spectroscopy of Blue Compact Dwarfs
Lei Hao, Yanling Wu, V. Charmandaris, H. W. W. Spoon, J. Bernard-Salas, D. Devost, V. Lebouteiller, J. R. Houck, arXiv:0908.4084 [ps, pdf, other]
Comments: 15 pages, including 1 table and 14 figures. Accepted by ApJ

A Maximum Stellar Surface Density in Dense Stellar Systems
Philip F. Hopkins, Norman Murray, Eliot Quataert, Todd A. Thompson, arXiv:0908.4088 [ps, pdf, other]
Comments: 6 pages, 2 figures, submitted to MNRAS Letters

A Spatially Resolved Map of the Kinematics, Star-Formation and Stellar Mass Assembly in a Star-Forming Galaxy at z=4.9
Mark Swinbank, Tracy Webb, Johan Richard, Richard Bower, Richard Ellis, Garth Illingworth, Tucker Jones, Mariska Kriek, Ian Smail, Dan Stark, Pieter Van Dokkum, rXiv:0909.0111 [ps, pdf, other]
Comments: Accepted for publication in MNRAS. 11 pages, 7 figures

Is this the highest redshift starbursting galaxy with an identified outflow?

Quantitative determination of the AGN content in local ULIRGs through L-band spectroscopy
G. Risaliti, M. Imanishi, E. Sani, arXiv:0908.4544 [ps, pdf, other]
Comments: 8 Pages, 5 figures. Accepted for publication in MNRAS

Physical Conditions in the Low-Ionization Component of Starburst Outflows: The Shape of Near-Ultraviolet and Optical Absorption-Line Troughs in Keck Spectra of ULIRGs
Crystal L. Martin, Nicolas Bouche, arXiv:0908.4271 [ps, pdf, other]
Comments: 28 pages, 10 figures, to appear in ApJ

Very interesting and impressive work. The variation of the cloud covering fraction with velocity should prove a particularly powerful model discriminant.

The starburst-GRB connection
Jens Dreyer, Julia K. Becker, Wolfgang Rhode, arXiv:0909.0158 [ps, pdf, other]
Comments: 4 pages, 4 figures, contribution to the 31st ICRC, Lodz, Poland, 2009

Transport of cosmic rays in the nearby starburst galaxy NGC 253
Volker Heesen, Rainer Beck, Marita Krause, Ralf-Jürgen Dettmar, arXiv:0909.0282 [ps, pdf, other]
Comments: 6 pages, 9 figures, to be published in Astronomische Nachrichten (proceedings of Symposium 6 of the JENAM 2008, Vienna)

Tracing Star Formation in Cool Core Clusters with GALEX
Amalia Hicks, Richard F. Mushotzky, Megan Donahue, arXiv:0909.0257 [pdf, other]
4 pages, 4 figures; to appear in proceedings of The Monster's Fiery
Breath: Feedback in Galaxies, Groups, and Clusters (AIP conference

Local Luminous Infrared Galaxies: Spatially resolved mid-infrared observations with Spitzer/IRS
Almudena Alonso-Herrero, Miguel Pereira-Santaella, George H. Rieke, Luis Colina, Charles W. Engelbracht, Pablo Perez-Gonzalez, Tanio Diaz-Santos, J. D. T. Smith, arXiv:0909.0658 [ps, pdf, other]
Comments: Accepted for publication in Advances in Space Research

Numerical and Theoretical Astrophysics

Computational Eulerian Hydrodynamics and Galilean Invariance
Brant E. Robertson, Andrey V. Kravtsov, Nickolay Y. Gnedin, Tom Abel, Douglas H. Rudd, arXiv:0909.0513 [ps, pdf, other]
Comments: Submitted to MNRAS. Figures degraded. For high-resolution color figures and movies of the numerical simulations, please visit this http URL

From their abstract: "In this work, we critically examine recent claims [i.e. Springel 2009] that these methods violate Galilean invariance of the Euler equations. We demonstrate that Eulerian hydrodynamics methods do converge to a Galilean-invariant solution, provided a well-defined convergent solution exists. Specifically, we show that numerical diffusion, resulting from diffusion-like terms in the discretized hydrodynamical equations solved by Eulerian methods, accounts for the effects previously identified as evidence for the Galilean non-invariance of these methods."

Oct-tree Method on GPU
N.Nakasato, arXiv:0909.0541 [ps, pdf, other]
Comments: Poster paper to be appeared in SC09

Turbulence and Mixing in the Intracluster Medium
P. Sharma, B. D. G. Chandran, E. Quataert, I. J. Parrish, arXiv:0909.0270 [ps, pdf, other]
Comments: 8 pages, 2 figs., submitted to the conference proceedings of "The Monster's Fiery Breath;" a follow up of arXiv:0901.4786 focusing on the general mixing properties of the ICM

High Energy Astrophysics

Radial Distribution of X-ray Point Sources near the Galactic Center
Jaesub Hong, Maureen van den Berg, Jonathan E. Grindlay, Silas Laycock, arXiv:0908.4306 [ps, pdf, other]
Comments: 17 pages, 7 figures, 6 tables, accepted for publication in Astrophysical Journal

Stars. Supernovae and Planets

Atlas of Vega: 3850 -- 6860 Angstroms
Hyun-Sook Kim, Inwoo Han, G. Valyavin, Byeong-Cheol Lee, V. Shimansky, G.A. Galazutdinov, arXiv:0908.4081 [ps, pdf, other]
Comments: 9 pages, 1 table, 4 figures, accepted to be published in The Publications of the Astronomical Society of the Pacific (PASP)

Balmer-Dominated Shocks: A Concise Review

Kevin Heng, arXiv:0908.4080 [ps, pdf, other]
Comments: 20 pages, 7 figures (double-columned, font size 10). Submitted to PASA. Comments welcome


A Color All-Sky Panorama Image of the Milky Way
Axel Mellinger, arXiv:0908.4360 [pdf, other]
Comments: 7 figures, submitted to PASP

Wednesday, September 02, 2009

Quality of each US state's science standards evaluated. MD gets a C

Mead and Mates evaluate state science standards with respect to their treatment of evolution and cosmology:

Our survey indicates that science standards tend to cover evolution more extensively than they did a decade ago, and that the average quality of the treatment has increased. However, certain types of creationist language are also becoming more common in state standards. We also discuss the history and role of state science standards in American public education.
I'd assumed that the Mid-Atlantic and New England states would all do well, but Maryland only gets a C, along with New York and Maine, while Connecticut gets a D. PA surprisingly enough gets an A.

MD gets a C thanks to "No human evolution. Discussion of cosmology in earth and space standards lacking." Connecticut is even worse: "Human evolution has been dropped. Despite specific reference to evolution in PreK-8 framework, there is no mention of age of the earth, fossils, Big Bang theory, plate tectonics, etc. "

[Image taken from their paper.]

Mead, L.S. & Mates, A., 2009, Evolution: Education and Outreach, 2(3): 359-371.