Understanding the molecular outflow in NGC 1266

Understanding the molecular outflow in NGC 1266

by | Apr 15, 2011 | Daily Paper Summaries

Title: Discovery of an AGN-Driven Molecular Outflow in the Local Early-Type Galaxy NGC 1266 Authors: Katherine Alatalo, Leo Blitz, Lisa M. Young, Timothy A. Davis, Martin Bureau, Laura A Lopez, Michele Cappellari, Nicholas Scott, Kristen L. Shapiro, Alison F. Crocker, Sergio Martin, Maxime Bois, et al. First author’s institution: University of California, Berkeley Today’s astrobite deals with an exciting but puzzling observation of a local galaxy, NGC 1266.  These observations are exciting because they go against the standard lore of how galaxies form.  This particular galaxy has been classified as an S0, a type of galaxy associated with little gas and an old stellar population.  Most observers assume that S0 and elliptical galaxies are ‘red and dead’, that is, that they finished forming stars long ago and that the light we see mainly comes from older, low-mass stars that emit redder light than young, massive stars, which tend to dominate the light we see from star-forming galaxies.Recently, however, many studies have begun to find that S0s and ellipticals exhibit a low level of star formation and actually can host a significant amount of gas.  This paper is part of the ATLAS3D project, which aims to infer the atomic and molecular gas content as well as the stellar kinematics of a sample of ‘red and dead’ elliptical and S0 galaxies.  This particular paper makes use of multiwavelength data that span the electromagnetic spectrum from radio to x-rays.  Perhaps most interesting are the submillimeter observations from the IRAM 30m telescope in southern Spain, the CARMA submillimeter array in Owens Valley California, and the SMA array on top of Mauna Kea on the Big Island of Hawaii. The submillimeter observations trace the molecular gas content...
Installing and Running Gadget-2

Installing and Running Gadget-2

by | Apr 2, 2011 | Career Navigation

This is the first of two posts detailing how to install and operate the Gadget-2 hydrodynamics code. Click here for the second post in the series.Today’s astrobite will be another in a series on career advice and useful astronomical tools.  So far, it looks like there’s been a dearth of posts on the tools of theoretical astrophysics, so I thought I’d take the opporunity to show how easy it is to run a simulation using Gadget-2, a smoothed particle hydrodynamics (or SPH) code.  Gadget-2 is open source and publically available, so anyone can run simulations with it.  In a future post, I’ll discuss how to set up and run a simple hydrodynamics test problem.The instructions for installing Gadget-2 will be highly platform dependent.  If you’re running Linux or UNIX, you have all of the tools you will need to compile the codes already. If you’re on a Mac, you’ll need to install and update Xcode, which includes all of the compilers you will need.  On Windows, you’ll probably need to install cygwin which will give your Windows installation full UNIX support. Since I have a Mac, I’m going to focus on getting these codes working on OS X Snow Leopard.  If you have a different system, it might not be possible to follow my instructions exactly.  I’ll be doing all of the simulations for this series of posts on my laptop, a Macbook Pro.First, you will need to download a few software packages. Gadget 2.0.7. Version 1.9 of the GNU scientific library (GSL). Version 2.1.5 of the FFTW fast Fourier transform library. A Message Passing Interface (MPI) library such...