My first “turno” at ALMA

My first “turno” at ALMA

by | Jan 29, 2012 | Personal Experiences

Note: This is the first astrobite in what I hope will be a periodic series about my adventures doing astronomy research in a foreign country. I’ll be living and doing research in Santiago, Chile, for one year with funding from the Fulbright Commission for Educational Exchange Between the USA and Chile. Taking advantage of this opportunity to be in Chile during commissioning and Early Science of the ALMA Observatory, I’m spending three months as a visiting scientist in the “Commissioning and Science Verification” (CSV) group of ALMA. For details on ALMA (the Atacama Large Millimeter/submillimeter Array), check out the website. During my time with CSV, I will spend 8 day “turnos” (or shifts) at the ALMA Operations Support Facility (OSF) in the Atacama Desert, one of the driest places in the world and really quite spectacular! The rest of my time with ALMA will be spent at the Santiago Central Offices (SCO) working on data reduction and analysis in preparations for ALMA “Full Science” (see results from ALMA Early Science in this astrobite). Here I will describe one day of my first turno. This time, I’m working the “day shift”, which begins in the afternoon and runs until midnight.11:00 am — Good morning (it’s still morning…)! Time to take a walk around, maybe I will hit the gym. Of course, exercising either the mind or the body can be a challenge at an elevation of 2900 meters (about 10,000 feet). At least we’re not up with the antennas at 5000 meters!12:20 pm — Quick shower. Quick for two reasons: (1) Water is scarce in the Atacama Desert, so we...
Careers 101 Workshop

Careers 101 Workshop

by | Jan 10, 2012 | Career Navigation

The Monday morning workshop “Careers 101” at the AAS Austin meeting provided a room full of graduate students with several important aspects to ponder when considering our potential career paths, as well as some action advice to follow to develop our careers in the direction that we choose. I blogged a summary of the workshop here, and promised to follow up with some more specific details. I invite comments on this post, if you have any suggestions or advice you would like to contribute related to astronomy career paths.The workshop was organized around a panel, introduced and moderated by Alaina Levine (founder of Quantum Success Solutions).Panelists: Dawn Gelino (NASA Exoplanet Science Institute) Adam Kraus (Hubble Postdoctoral Fellow) Edward Ajhar (NSF Program Officer) Anita Cochran (Assistant Director of McDonald Observatory) Joe Bernstein (Argonne National Lab)Advice (in no particular order): 1. Network. Establish your brand, realizing that at every stage of your career you can be the world’s expert on a niche subject at some level. Find confidence in this.2. Make yourself stand out. If you are in a collaboration (especially if it is a large collaboration), take ownership of some aspect of the science.3. Prove yourself by earning your own grants and fellowships. Writing proposals is good experience, even as a grad student or postdoc.4. Think about what will make you happy. Is an R1 research career, tenure track, what you would enjoy doing? Ask others, do some soul searching. Keep in mind that only 1 in 4 of us will get a tenure track position. Whatever you decide, you CAN change your mind later, but you should start on...

Black holes and “no-hair”?

by | Dec 9, 2011 | Daily Paper Summaries

Paper title: Verifying the no-hair property of massive compact objects with intermediate-mass-ratio inspirals in advanced gravitational-wave detectors Authors: Carl L. Rodriguez, Ilya Mandel, Jonathan R. Gair First Author’s Affiliation: Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) & Dept. of Physics and Astronomy, Northwestern UniversityThese authors propose that advanced gravitational wave detectors will be able to directly detect the coalescence of compact objects, such as neutron stars (NS) and black holes (BH). The gravitational waves resulting when a neutron star or stellar-mass black hole inspirals into an intermediate-mass black hole give interesting information about gravitational physics (go here to watch cool videos of BHs colliding). The goal is to directly test general relativity (a review paper is found here).A significant advance in this field comes from the next generation of detectors and experiments. Two such observatories are Advanced LIGO (Laser Interferometer Gravitational-wave Observatory, a project with two interferometers in Washington and one in Louisiana) and Virgo (near Pisa, Italy). Advanced LIGO should achieve sufficient sensitivity by 2015 to detect compact binaries as they interact and coalesce. This paper specifically develops the technique to detect high-mass systems with a total mass in the range of 25 to 100 solar masses, where one component is greater than one solar mass and the other less than 99 solar masses. The systems in this study are called Intermediate-mass-ratio inspirals (IMRIs) because the mass ratios between the two objects (the more massive object at the center and the object spiraling inward) are between 10:1 and 100:1.Do objects like this really exist? Observational and theoretical models suggest the presence of intermediate-mass black holes (IMBHs)...
What you need to know about SPH

What you need to know about SPH

by | Nov 11, 2011 | Daily Paper Summaries

Paper title: Smoothed Particle Hydrodynamics: Things I wish my mother taught me Author: D. J. Price Author’s Affiliation: Monash Centre for Astrophysics (MoCA), School of Mathematical Sciences, Monash University, Vic 3800, AustraliaThe title of this article caught my eye on the arXiv for two reasons: rarely do authors mention their mother in a paper, and like the author I also wished that my mother (or anyone) had taught me about smoothed particle hydrodynamics. The author soon clarifies that actually it was his PhD supervisor, not his mother, who he wishes had taught him the important details related to simulations, so in fact the rest of the paper pays no further attention to family ties. But, the subject of smoothed particle hydrodynamics (SPH) still fascinates me, and seems to be extremely relevant to current astronomy, so I will summarize the topic here. I should also make the disclaimer that I have never used SPH, so what I present is merely what I have learned from reading the paper.Fundamentals: SPH is a computational method used to model flows, and it is used in a variety of subjects including astrophysics and oceanography. It begins with a known distribution of point-mass particles, and computes density such that density is independent of the following particle characteristics: (1) the absolute positions of the particles, (2) arbitrary rotations, and (3) histories of the particles. Summing up the density comprises what the author calls the fundamental axiom of SPH, as it use discrete particles of fixed mass to describe fluid properties. The resolution of the method (or the smallest step-size that one can take) depends on the...