Wine and Cheese Fall 2015 - Revision history

Tlan: /* Henry Ferguson */

2015-12-07T16:34:16Z

Henry Ferguson

← Older revision		Revision as of 16:34, 7 December 2015
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	'''CANDELS: Observing Galaxy Assembly'''		'''CANDELS: Observing Galaxy Assembly'''

	This talk will present an update on the findings from the CANDELS survey, which occupied		This talk will present an update on the findings from the CANDELS survey, which occupied about 4 months of Hubble observing time spread out over 2011-2013. The observations targeted the deepest multi-wavelength survey fields, with the aim of documenting the first third of galactic evolution from redshift z~8 to z~1.5. This talk will summarize some of the recent findings from the survey, highlighting both emerging insights on the physics of galaxy evolution as well as open questions that will motivate observations from JWST.
	about 4 months of Hubble observing time spread out over 2011-2013. The observations
	targeted the deepest multi-wavelength survey fields, with the aim of documenting the
	first third of galactic evolution from redshift z~8 to z~1.5. This talk will summarize some
	of the recent findings from the survey, highlighting both emerging insights on the physics
	of galaxy evolution as well as open questions that will motivate observations from JWST.

Tlan: /* Henry Ferguson */

2015-12-07T16:22:55Z

Henry Ferguson

← Older revision		Revision as of 16:22, 7 December 2015
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	= December 14th =		= December 14th =
	== Henry Ferguson ==		== Henry Ferguson ==
	''~~Full seminar talk~~'' ~~<p>~~		'''CANDELS: Observing Galaxy Assembly'''
	~~Title and abstract coming soon~~.
			This talk will present an update on the findings from the CANDELS survey, which occupied
			about 4 months of Hubble observing time spread out over 2011-2013. The observations
			targeted the deepest multi-wavelength survey fields, with the aim of documenting the
			first third of galactic evolution from redshift z~8 to z~1.5. This talk will summarize some
			of the recent findings from the survey, highlighting both emerging insights on the physics
			of galaxy evolution as well as open questions that will motivate observations from JWST.

Tlan: /* Eve Ostriker */

2015-12-01T21:17:01Z

Eve Ostriker

← Older revision		Revision as of 21:17, 1 December 2015
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	= December 7th =		= December 7th =
	== Eve Ostriker ==		== Eve Ostriker ==
	''Quantifying star formation feedback and self-regulation'' ~~<p>~~		'''Quantifying star formation feedback and self-regulation'''

	The character of the multiphase interstellar medium (ISM), both in our own Milky Way and in other gas-rich spirals and dwarfs, is largely controlled by the “feedback” from massive stars. Massive stars heat the local and distant ISM through their radiation, and help to destroy their birth clouds through the impact of radiation forces and winds. When massive stars die, supernova blast waves expand over huge volumes, producing the hot ISM phase and driving turbulence in the warm and cold ISM phases. Since feedback effects create the chief opposition to gravitational collapse at all scales, the inevitable conclusion is that star formation must be self-regulated. Quantifying star formation self-regulation theoretically is challenging due to the wide range of scales and complexity of the physics involved, and this difficultly is particularly acute for modeling evolution on cosmic scales. In recent years, however, it has become possible to study star formation and feedback effects self-consistently on sub-pc to kpc scales within galaxies, using direct numerical radiation/magneto/hydrodynamic simulations. I will discuss theory and numerical simulations that explain physically how self-regulated star formation operates, and provide quantitative predictions for the cloud-scale star formation efficiency in GMCs, and the large-scale star formation rates in disk galaxies. Because the ISM is largely turbulence-supported, understanding what drives gas motions is crucial. At cloud scales, radiation hydrodynamic simulations show that radiation feedback is less effective in ejecting mass from GMCs than previously thought, potentially explaining high observed star formation efficiency in extreme environments. At galactic scales, feedback from supernovae dominates, because the momentum injected by Sedov-Taylor blast waves is an order of magnitude greater than other source terms. Resolved simulations show that each supernova blast robustly provides momentum ~ 1 - 4 e5 Msun km/s to the ISM, and this level of feedback explains star formation rates in wide range of galactic systems. Simultaneously, self-regulated star formation leads to ISM thermal, turbulent, and		The character of the multiphase interstellar medium (ISM), both in our own Milky Way and in other gas-rich spirals and dwarfs, is largely controlled by the “feedback” from massive stars. Massive stars heat the local and distant ISM through their radiation, and help to destroy their birth clouds through the impact of radiation forces and winds. When massive stars die, supernova blast waves expand over huge volumes, producing the hot ISM phase and driving turbulence in the warm and cold ISM phases. Since feedback effects create the chief opposition to gravitational collapse at all scales, the inevitable conclusion is that star formation must be self-regulated. Quantifying star formation self-regulation theoretically is challenging due to the wide range of scales and complexity of the physics involved, and this difficultly is particularly acute for modeling evolution on cosmic scales. In recent years, however, it has become possible to study star formation and feedback effects self-consistently on sub-pc to kpc scales within galaxies, using direct numerical radiation/magneto/hydrodynamic simulations. I will discuss theory and numerical simulations that explain physically how self-regulated star formation operates, and provide quantitative predictions for the cloud-scale star formation efficiency in GMCs, and the large-scale star formation rates in disk galaxies. Because the ISM is largely turbulence-supported, understanding what drives gas motions is crucial. At cloud scales, radiation hydrodynamic simulations show that radiation feedback is less effective in ejecting mass from GMCs than previously thought, potentially explaining high observed star formation efficiency in extreme environments. At galactic scales, feedback from supernovae dominates, because the momentum injected by Sedov-Taylor blast waves is an order of magnitude greater than other source terms. Resolved simulations show that each supernova blast robustly provides momentum ~ 1 - 4 e5 Msun km/s to the ISM, and this level of feedback explains star formation rates in wide range of galactic systems. Simultaneously, self-regulated star formation leads to ISM thermal, turbulent, and

Tlan: /* Eve Ostriker */

2015-12-01T21:16:46Z

Eve Ostriker

← Older revision		Revision as of 21:16, 1 December 2015
Line 182:		Line 182:
	= December 7th =		= December 7th =
	== Eve Ostriker ==		== Eve Ostriker ==
	''~~Full seminar talk~~'' <p>		''Quantifying star formation feedback and self-regulation'' <p>
	~~Title~~ and ~~abstract coming soon~~.
			The character of the multiphase interstellar medium (ISM), both in our own Milky Way and in other gas-rich spirals and dwarfs, is largely controlled by the “feedback” from massive stars. Massive stars heat the local and distant ISM through their radiation, and help to destroy their birth clouds through the impact of radiation forces and winds. When massive stars die, supernova blast waves expand over huge volumes, producing the hot ISM phase and driving turbulence in the warm and cold ISM phases. Since feedback effects create the chief opposition to gravitational collapse at all scales, the inevitable conclusion is that star formation must be self-regulated. Quantifying star formation self-regulation theoretically is challenging due to the wide range of scales and complexity of the physics involved, and this difficultly is particularly acute for modeling evolution on cosmic scales. In recent years, however, it has become possible to study star formation and feedback effects self-consistently on sub-pc to kpc scales within galaxies, using direct numerical radiation/magneto/hydrodynamic simulations. I will discuss theory and numerical simulations that explain physically how self-regulated star formation operates, and provide quantitative predictions for the cloud-scale star formation efficiency in GMCs, and the large-scale star formation rates in disk galaxies. Because the ISM is largely turbulence-supported, understanding what drives gas motions is crucial. At cloud scales, radiation hydrodynamic simulations show that radiation feedback is less effective in ejecting mass from GMCs than previously thought, potentially explaining high observed star formation efficiency in extreme environments. At galactic scales, feedback from supernovae dominates, because the momentum injected by Sedov-Taylor blast waves is an order of magnitude greater than other source terms. Resolved simulations show that each supernova blast robustly provides momentum ~ 1 - 4 e5 Msun km/s to the ISM, and this level of feedback explains star formation rates in wide range of galactic systems. Simultaneously, self-regulated star formation leads to ISM thermal, turbulent, and
			magnetic pressures that are in good agreement with observations.

	= December 14th =		= December 14th =

Tlan: /* Mei-Ling Huang */

2015-11-29T23:56:40Z

Mei-Ling Huang

← Older revision		Revision as of 23:56, 29 November 2015
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	== Mei-Ling Huang ==		== Mei-Ling Huang ==
	~~Title~~ and ~~abstract coming soon~~.		'''The variation in molecular gas depletion time among nearby galaxies'''

			One of the most fundamental questions in modern astrophysics is how galaxies convert their gas into stars, and how this process may change with the galaxy internal properties and/or across cosmic time. I will present the study of variations in molecular gas depletion time using a data set of nearby galaxies drawn from the HERACLES, ATLAS3D, and COLD GASS surveys. I will demonstrate that the primary global parameter correlation is between depletion time and sSFR; all other remaining correlations can be shown to be induced by this primary dependence. I will also discuss molecular gas depletion time in galaxy structures such as bulges, grand-design spiral arms, bars and rings.

	= December 7th =		= December 7th =

Tlan at 00:21, 29 November 2015

2015-11-29T00:21:44Z

← Older revision		Revision as of 00:21, 29 November 2015
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	== Brian Cherinka ==		== Brian Cherinka ==
	'''Visually Exploring Astronomical Data + Other Things'''		'''Visually Exploring Astronomical Data + Other Things'''

	I will discuss a variety of ideas, at various stages of implementation, relating to streamlining the path to astronomy science, the visual exploration of data as outliers, outreach, and education.		I will discuss a variety of ideas, at various stages of implementation, relating to streamlining the path to astronomy science, the visual exploration of data as outliers, outreach, and education.

Tlan at 00:21, 29 November 2015

2015-11-29T00:21:29Z

← Older revision		Revision as of 00:21, 29 November 2015
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	= November 30th =		= November 30th =
	== Brian Cherinka ==		== Brian Cherinka ==
	~~Title~~ and ~~abstract coming soon~~.		'''Visually Exploring Astronomical Data + Other Things'''
			I will discuss a variety of ideas, at various stages of implementation, relating to streamlining the path to astronomy science, the visual exploration of data as outliers, outreach, and education.


	== Mei-Ling Huang ==		== Mei-Ling Huang ==

Tlan at 16:40, 10 November 2015

2015-11-10T16:40:28Z

@@ Line 144: / Line 144: @@
 = November 16th =
 == Fabienne Bastien ==
-Title and abstract coming soon.
+'''Convection in Cool Stars, as Revealed through Stellar Brightness Variations'''
 == Ai-Lei Sun ==

Tlan at 21:13, 3 November 2015

2015-11-03T21:13:11Z

← Older revision		Revision as of 21:13, 3 November 2015
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	== Eric Switzer ==		== Eric Switzer ==
	''Full seminar talk'' <p>		''Full seminar talk'' <p>
	'''Cosmic tomography with the GBT and status of the Primordial Inflation Polarization ExploreR (PIPER)'''		'''Cosmic tomography with the GBT and status of the Primordial Inflation Polarization ExploreR (PIPER)''' <br>

	Intensity mapping has attracted significant attention as a method for efficiently surveying cosmological volumes out to high redshift. I will describe results from the GBT HI intensity mapping survey, which detected 21 cm emission in cross-correlation with WiggleZ, and demonstrated suppression of foregrounds from ~1 K to < 1 mK, approaching the level of the signal. From these measurements, we infer the product of HI abundance and bias at z~0.8. This complements DLA measurements of the abundance, which are expensive at these redshifts, and it extends HI abundance inferred from 21 cm emission of discrete sources at z~0. Analysis of these intensity mapping data required new methods that are robust to instrumental response to bright foregrounds. I will then describe the Primordial Inflation Polarization ExploreR (PIPER) balloon-borne telescope. PIPER will measure the CMB polarization at 200, 270, 350, and 600 GHz across 85% of the sky, seeking the B-mode signature of inflationary gravitational waves on large angular scales. I will describe some of the unique approaches in the experiment and report on the status of hardware at GSFC.		Intensity mapping has attracted significant attention as a method for efficiently surveying cosmological volumes out to high redshift. I will describe results from the GBT HI intensity mapping survey, which detected 21 cm emission in cross-correlation with WiggleZ, and demonstrated suppression of foregrounds from ~1 K to < 1 mK, approaching the level of the signal. From these measurements, we infer the product of HI abundance and bias at z~0.8. This complements DLA measurements of the abundance, which are expensive at these redshifts, and it extends HI abundance inferred from 21 cm emission of discrete sources at z~0. Analysis of these intensity mapping data required new methods that are robust to instrumental response to bright foregrounds. I will then describe the Primordial Inflation Polarization ExploreR (PIPER) balloon-borne telescope. PIPER will measure the CMB polarization at 200, 270, 350, and 600 GHz across 85% of the sky, seeking the B-mode signature of inflationary gravitational waves on large angular scales. I will describe some of the unique approaches in the experiment and report on the status of hardware at GSFC.

Tlan at 21:12, 3 November 2015

2015-11-03T21:12:38Z

← Older revision		Revision as of 21:12, 3 November 2015
Line 139:		Line 139:
	''Full seminar talk'' <p>		''Full seminar talk'' <p>
	'''Cosmic tomography with the GBT and status of the Primordial Inflation Polarization ExploreR (PIPER)'''		'''Cosmic tomography with the GBT and status of the Primordial Inflation Polarization ExploreR (PIPER)'''

	Intensity mapping has attracted significant attention as a method for efficiently surveying cosmological volumes out to high redshift. I will describe results from the GBT HI intensity mapping survey, which detected 21 cm emission in cross-correlation with WiggleZ, and demonstrated suppression of foregrounds from ~1 K to < 1 mK, approaching the level of the signal. From these measurements, we infer the product of HI abundance and bias at z~0.8. This complements DLA measurements of the abundance, which are expensive at these redshifts, and it extends HI abundance inferred from 21 cm emission of discrete sources at z~0. Analysis of these intensity mapping data required new methods that are robust to instrumental response to bright foregrounds. I will then describe the Primordial Inflation Polarization ExploreR (PIPER) balloon-borne telescope. PIPER will measure the CMB polarization at 200, 270, 350, and 600 GHz across 85% of the sky, seeking the B-mode signature of inflationary gravitational waves on large angular scales. I will describe some of the unique approaches in the experiment and report on the status of hardware at GSFC.		Intensity mapping has attracted significant attention as a method for efficiently surveying cosmological volumes out to high redshift. I will describe results from the GBT HI intensity mapping survey, which detected 21 cm emission in cross-correlation with WiggleZ, and demonstrated suppression of foregrounds from ~1 K to < 1 mK, approaching the level of the signal. From these measurements, we infer the product of HI abundance and bias at z~0.8. This complements DLA measurements of the abundance, which are expensive at these redshifts, and it extends HI abundance inferred from 21 cm emission of discrete sources at z~0. Analysis of these intensity mapping data required new methods that are robust to instrumental response to bright foregrounds. I will then describe the Primordial Inflation Polarization ExploreR (PIPER) balloon-borne telescope. PIPER will measure the CMB polarization at 200, 270, 350, and 600 GHz across 85% of the sky, seeking the B-mode signature of inflationary gravitational waves on large angular scales. I will describe some of the unique approaches in the experiment and report on the status of hardware at GSFC.