Monday.
1211.0273
Proper motions of young stellar outflows in the mid-infrared with Spitzer (IRAC). I. The NGC 1333 region
?? (author missing)
* Herbig-Hary objects (HH): small patches of nebulosity associated with newly born stars; formed when narrow jets of gas ejected by young stars collide with clouds of gas and dust nearby at speeds of several hundred km/s. HH are ubiquitous in SF regions, and several are often seen around a single star, aligned along its rotational axis. They are transient phenomena, lasting not more than a few thousand years. They can evolve visibly over a short timescale. A distinct type of emission nebula.
* NGC 1333 is a reflection nebula in the constellation Perseus, belonging to the Per molecular cloud.
2.5 um maps over 7 yr interval to determine proper motion of its associated outflows; first successful attempt at obtaining proper motions of stellar outflow with Spitzer. Outflow from Herbig-Haro objects; proper motion of 9-13 km/s; consistent with previously determined optical proper motions. 8 outflows in total measured, range from 10-100 km/s. Derived proper motions show that 3 have tangential velocities <= 20 km/s. This result shows that a large fraction of the observed outflows have low intrinsic velocities, and that the low proper motions are not merely a projection effect.
1211.0278
Moderate-luminosity growing black holes from 1.25<z<2.7: varied accretion in disk-dominated hosts
Simmons, Urry, Schawinski, Cardamone, Glikman
57 AGN from GOODS-S: compute M_BH and L_BH from X-ray emission. Determine host galaxy morphological parameters: separate galaxies from their central point sources in deep HST images, and host stellar masses and colors by multi-wavelength SED fitting. 90% of GOODS AGN at these redshifts have detected rest-frame optical nuclear point sources; bolometric luminosities range from 2d43-2e46 erg/s. BHs growing at a range of accretion rates, with at least 50% of the sample having L/L_Edd < 0.1. 70% of host galaxies have stellar masses M*>1e10 Msun, with a range of colors suggesting a complex SFH. Find no evolution of AGN bolometric luminosity within the sample, and no correlation between AGN bolometric luminosity and host stellar mass, color or morphology. Fuly half the sample of host galaxies is disk-dominated, with another 25% having strong disk components. <15% of the systems appear to be at some stage of a major merger. These moderate-luminosity AGN hosts are therefore inconsistent with a dynamical history dominated by mergers strong enough to destroy disks, indicating minor mergers or secular processes dominate the co-evolution of galaxies and their central BHs at z~2.
1211.0279
Berkeley supernova Ia program V: late-time spectra of type Ia supernovae
Silverman, Ganeshalingam, Filippenko
t>100d optical spectra of z<0.1 SNIa (34 samples with 60 nebular spectra). FWHM and velocities of Fe III, Fe II, and Ni II emission features measured in most of the spectra, with S/N>20/px, and older than 160d past maximum. Velocities of all 3 features relatively constant with time, increasing only a few to ~20 km/s/d. The nebular velocity (avg of Fe II and Ni II) is correlated with the velocity gradient and near-maximum-brightness photospheric velocity; most high velocity gradient objects have redshifted nebular lines while most low velocity gradient objects have blueshifted nebular lines [why?]. A marginal correlation is found between v_neb and Delta m_15(B) [?]. Evidence for light echoes found in handful of objects, though not confirmed.
1211.0280
A strongly-lensed massive ultra-compact quiescent galaxy at z~2.4 in the COSMOS/UltraVISTA field
Muzzin, .. Franx, van Dokkum, ... et al
As the title says. Photo-z (27 band) determined. Lensing factor 4-5. Constrain size and Sersic profile of the galaxy. The best-fit stellar pop model is a massive galaxy with an age of 1 Gyr, moderate dust extinction, and a low sSFR. Typical massive "Red-and-dead" galaxies at this redshift.
1211.0285
Addressing decadal survey science through community access to highly multiplexed spectroscopy with BigBOSS on the KPNO Mayall Telescope
Pilachowski et al
Summary of potential science impact of Mayall+BigBOSS. Determine cosmological params, community access component: origin and evolution of galaxies, stars, IGM. Massive spectroscopy is the critical missing ingredient in numerous ongoing and planned ground- and space-based surveys, and BigBOSS is unique to provide this to the US community.
1211.0287
Measures of galaxy environment -- II. Rank-ordered mark correlations
Skibba, Sheth, ... et al
Analyze environmental correlations using mark clustering statistics with mock galaxy catalogue. Mark correlation functions are able to detect even a small dependence of galaxy properties on the environment, quantified by the overdensity 1+delta, while such a small dependence would be difficult to detect by traditional methods. Then show that rank ordering the marks and using the rank as a weight is a simple way of comparing the correlation signals for different marks. WIth this, quantify to what extent fixed-aperture overdensities are sensitive to large-scale halo environments, nearest-neighbor overdensities are sensitive to small-scale environments within haloes, and color is a better tracer of overdenisty than is luminosity [based on what SAM?].
1211.0310
Large synoptic survey telescope: dark energy science collaboration
LSST DE science collaboration
3 year work plan for DE science. Analysis WG: WL, LSS, clusters, SNIa, and SL. Computing WG: cosmo sims, galaxy catalogs, photon simulations, and systematic SW and computational framework for data analysis. Technical WGs: make connection between DE science and LSST system. The WGs have close linkages, especially through the use of the photon simulations to study the impact of instrument design and survey strategy on analysis methodology and cosmological parameter estimation. The WP describes several high-priority tasks identified by each of the 16 working groups.
1211.0326
The effect of models of the interstellar media on the central mass distribution of galaxies
Christensen et al
Compare central mass distribution of galaxies with 3 different ISM models with increasing complexity: primordial (H+He) cooling down to 1e4K, additional cooling via metal lines and to lower temperatures, and molecular hydrogen (H2) with shielding of atomic and molecular hydrogen in addition to metal line cooling. In order to analyze the effect of these models, follow the evolution of 4 field galaxies with V_peak< 120 km/s to a redshift of zero using high-res SPH sims in a fully cosmo LCDM context. The spiral galaxies produced in simulations with either primordial cooling or H2 physics have bulge magnitudes and scale lengths very similar to observed galaxies and realistic, rising rotation curves. In contrast, the metal line cooling simulation produced galaxies with more massive and concentrated bulges and with the peaked rotation curves typical of most previous LCDM simulations of spiral galaxies. The less-massive bulges and non-peaked rotation curves in the galaxies simulated with primordial cooling or H2 are linked to changes in the angular momentum distribution of the baryons. These galaxies had smaller amounts of low-angular momentum baryons because of increased gas loss from stellar feedback. When there is only primordial cooling, the SF gas is hotter and the feedback-heated gas cools more slowly than when metal line is cooling is included, and so requires less energy to be expelled. When H2 is included, the accompanying shielding produces large amounts of clumpy, cold gas where H2 forms. SF in clumpy gas results in more concentrated SNe feedback and greater efficiency of mass loss. The higher feedback efficiency causes a decrease of low-angular momentum material and formation of realistic bulges.
1211.0362
Lithium-rich stars in the SLoan Digital Sky Survey
Martell, Shetrone
Found, covers a borad range in mass and evolutionary phase, including bright giants and post-AGB stars. But process responsible for preserving or producing excess lithium in a small fraction of evolved stars remains unclear.
1211.0369
Modern view of the warm ionized medium
Hill et al
Review the observational evidence of WIM, a major and physically distinct component of the Galactic ISM.
1211.0494
Transition from galactic to extragalactic cosmic rays
Aloisio et al
3 models of transition: ankle, dip and mixed composition models.
1211.0528
AGN environments: is the viewing angle sufficient to explain the difference between broad-ine and narrow-line AGN? == A low-redshift study of close AGN neighbours. Paper I
Villarroel, Korn, Matsuoka
Lack of intrinsic luminosity of objects makes it hard to test the AGN unification model. 1.6k Type-1 (borad-line) AGN-galaxy pairs, and 5.7k Type-2 AGN-galaxy pairs with spec-z studied, with projected distance of 350 kpc. Morphologies of AGN host galaxies derived from Galaxy Zoo project. Results suggest that broad-line AGN and narrow-line AGN reside in widely different environemnts where the neighbors to type-2s are more star forming and bluer than Type-1. There is a colour-dependency only detectable in the neighbors with photometric redshifts for the type-2 AGN. The ration between Type-1/Type-2 neighbors to Type-2 AGN decreases steadily at short separations with a statistical significance of 4.5 sigma [ratio of what? color?]. The lack of change in the morphology of the Type-2 AGN hosts having a close companion (contrary to the case of Type-1 AGN hosts) suggests that the innate state of Type-2 AGN is extremely short-lived and is not preserved in subsequent mergers. Finally, preform a hypothetical luminosity test to investigate whether a mass bias in our selection could explain the observed differences in the samples. Conclusion: AGN unification is consistently not supported by the environment of the two types of AGN, but that an evolutionary connection between them might exist.
1211.0532
Toward more realistic forecasting of dark energy constraints from galaxy redshift surveys
Want, Chuang, Hirata
Improve forecasting of DE constraints from galaxy z surveys by using the "dewiggled" galaxy power spectrum, P_dw(k), in the Fisher matrix calculations; it is a good fit to real galaxy clustering data over most of the scale range of interest. Find: new approach gives results in excellent agreement when compared to the results from the actual data analysis of the clustering of SDSS DR7 LRGs. Forecasts for stage IV surveys.
1211.0536
Dwarf galaxies and the Cosmic web
Benitez-Llambay, Navarro, et al
Use cosmological simulation of the formation of local group of galaxies to identify a mechanism that enables the removal of baryons from low-mass haloes without appealing to feedback or reionization. As the LG forms, matter bound to it forms a network of filaments and pancakes. This moving web of gas and DM drifts and sweeps a large volume, overtaking many haloes in the process. The DM content of these haloes is unaffected byt their gas can be efficiently removed by ram-pressure. The loss of gas is especially pronounced in low-mass haloes due to their lower binding energy, and has a dramatic effect on the SFH of affected systems. This "cosmic web stripping" may help to explain the scarcity of dwarf galaxies compared with the numerous low-mass haloes expected in LCDM and the large diversity of SFH and morphologies characteristic of faint galaxies. Although results are based on a single high-res sim, it is likely that the hydro interaction of dwarf galaxies with the cosmic web is a crucial ingredient so far missing from galaxy formation models.
1211.0273
Proper motions of young stellar outflows in the mid-infrared with Spitzer (IRAC). I. The NGC 1333 region
?? (author missing)
* Herbig-Hary objects (HH): small patches of nebulosity associated with newly born stars; formed when narrow jets of gas ejected by young stars collide with clouds of gas and dust nearby at speeds of several hundred km/s. HH are ubiquitous in SF regions, and several are often seen around a single star, aligned along its rotational axis. They are transient phenomena, lasting not more than a few thousand years. They can evolve visibly over a short timescale. A distinct type of emission nebula.
* NGC 1333 is a reflection nebula in the constellation Perseus, belonging to the Per molecular cloud.
2.5 um maps over 7 yr interval to determine proper motion of its associated outflows; first successful attempt at obtaining proper motions of stellar outflow with Spitzer. Outflow from Herbig-Haro objects; proper motion of 9-13 km/s; consistent with previously determined optical proper motions. 8 outflows in total measured, range from 10-100 km/s. Derived proper motions show that 3 have tangential velocities <= 20 km/s. This result shows that a large fraction of the observed outflows have low intrinsic velocities, and that the low proper motions are not merely a projection effect.
1211.0278
Moderate-luminosity growing black holes from 1.25<z<2.7: varied accretion in disk-dominated hosts
Simmons, Urry, Schawinski, Cardamone, Glikman
57 AGN from GOODS-S: compute M_BH and L_BH from X-ray emission. Determine host galaxy morphological parameters: separate galaxies from their central point sources in deep HST images, and host stellar masses and colors by multi-wavelength SED fitting. 90% of GOODS AGN at these redshifts have detected rest-frame optical nuclear point sources; bolometric luminosities range from 2d43-2e46 erg/s. BHs growing at a range of accretion rates, with at least 50% of the sample having L/L_Edd < 0.1. 70% of host galaxies have stellar masses M*>1e10 Msun, with a range of colors suggesting a complex SFH. Find no evolution of AGN bolometric luminosity within the sample, and no correlation between AGN bolometric luminosity and host stellar mass, color or morphology. Fuly half the sample of host galaxies is disk-dominated, with another 25% having strong disk components. <15% of the systems appear to be at some stage of a major merger. These moderate-luminosity AGN hosts are therefore inconsistent with a dynamical history dominated by mergers strong enough to destroy disks, indicating minor mergers or secular processes dominate the co-evolution of galaxies and their central BHs at z~2.
1211.0279
Berkeley supernova Ia program V: late-time spectra of type Ia supernovae
Silverman, Ganeshalingam, Filippenko
t>100d optical spectra of z<0.1 SNIa (34 samples with 60 nebular spectra). FWHM and velocities of Fe III, Fe II, and Ni II emission features measured in most of the spectra, with S/N>20/px, and older than 160d past maximum. Velocities of all 3 features relatively constant with time, increasing only a few to ~20 km/s/d. The nebular velocity (avg of Fe II and Ni II) is correlated with the velocity gradient and near-maximum-brightness photospheric velocity; most high velocity gradient objects have redshifted nebular lines while most low velocity gradient objects have blueshifted nebular lines [why?]. A marginal correlation is found between v_neb and Delta m_15(B) [?]. Evidence for light echoes found in handful of objects, though not confirmed.
1211.0280
A strongly-lensed massive ultra-compact quiescent galaxy at z~2.4 in the COSMOS/UltraVISTA field
Muzzin, .. Franx, van Dokkum, ... et al
As the title says. Photo-z (27 band) determined. Lensing factor 4-5. Constrain size and Sersic profile of the galaxy. The best-fit stellar pop model is a massive galaxy with an age of 1 Gyr, moderate dust extinction, and a low sSFR. Typical massive "Red-and-dead" galaxies at this redshift.
1211.0285
Addressing decadal survey science through community access to highly multiplexed spectroscopy with BigBOSS on the KPNO Mayall Telescope
Pilachowski et al
Summary of potential science impact of Mayall+BigBOSS. Determine cosmological params, community access component: origin and evolution of galaxies, stars, IGM. Massive spectroscopy is the critical missing ingredient in numerous ongoing and planned ground- and space-based surveys, and BigBOSS is unique to provide this to the US community.
1211.0287
Measures of galaxy environment -- II. Rank-ordered mark correlations
Skibba, Sheth, ... et al
Analyze environmental correlations using mark clustering statistics with mock galaxy catalogue. Mark correlation functions are able to detect even a small dependence of galaxy properties on the environment, quantified by the overdensity 1+delta, while such a small dependence would be difficult to detect by traditional methods. Then show that rank ordering the marks and using the rank as a weight is a simple way of comparing the correlation signals for different marks. WIth this, quantify to what extent fixed-aperture overdensities are sensitive to large-scale halo environments, nearest-neighbor overdensities are sensitive to small-scale environments within haloes, and color is a better tracer of overdenisty than is luminosity [based on what SAM?].
1211.0310
Large synoptic survey telescope: dark energy science collaboration
LSST DE science collaboration
3 year work plan for DE science. Analysis WG: WL, LSS, clusters, SNIa, and SL. Computing WG: cosmo sims, galaxy catalogs, photon simulations, and systematic SW and computational framework for data analysis. Technical WGs: make connection between DE science and LSST system. The WGs have close linkages, especially through the use of the photon simulations to study the impact of instrument design and survey strategy on analysis methodology and cosmological parameter estimation. The WP describes several high-priority tasks identified by each of the 16 working groups.
1211.0326
The effect of models of the interstellar media on the central mass distribution of galaxies
Christensen et al
Compare central mass distribution of galaxies with 3 different ISM models with increasing complexity: primordial (H+He) cooling down to 1e4K, additional cooling via metal lines and to lower temperatures, and molecular hydrogen (H2) with shielding of atomic and molecular hydrogen in addition to metal line cooling. In order to analyze the effect of these models, follow the evolution of 4 field galaxies with V_peak< 120 km/s to a redshift of zero using high-res SPH sims in a fully cosmo LCDM context. The spiral galaxies produced in simulations with either primordial cooling or H2 physics have bulge magnitudes and scale lengths very similar to observed galaxies and realistic, rising rotation curves. In contrast, the metal line cooling simulation produced galaxies with more massive and concentrated bulges and with the peaked rotation curves typical of most previous LCDM simulations of spiral galaxies. The less-massive bulges and non-peaked rotation curves in the galaxies simulated with primordial cooling or H2 are linked to changes in the angular momentum distribution of the baryons. These galaxies had smaller amounts of low-angular momentum baryons because of increased gas loss from stellar feedback. When there is only primordial cooling, the SF gas is hotter and the feedback-heated gas cools more slowly than when metal line is cooling is included, and so requires less energy to be expelled. When H2 is included, the accompanying shielding produces large amounts of clumpy, cold gas where H2 forms. SF in clumpy gas results in more concentrated SNe feedback and greater efficiency of mass loss. The higher feedback efficiency causes a decrease of low-angular momentum material and formation of realistic bulges.
1211.0362
Lithium-rich stars in the SLoan Digital Sky Survey
Martell, Shetrone
Found, covers a borad range in mass and evolutionary phase, including bright giants and post-AGB stars. But process responsible for preserving or producing excess lithium in a small fraction of evolved stars remains unclear.
1211.0369
Modern view of the warm ionized medium
Hill et al
Review the observational evidence of WIM, a major and physically distinct component of the Galactic ISM.
1211.0494
Transition from galactic to extragalactic cosmic rays
Aloisio et al
3 models of transition: ankle, dip and mixed composition models.
1211.0528
AGN environments: is the viewing angle sufficient to explain the difference between broad-ine and narrow-line AGN? == A low-redshift study of close AGN neighbours. Paper I
Villarroel, Korn, Matsuoka
Lack of intrinsic luminosity of objects makes it hard to test the AGN unification model. 1.6k Type-1 (borad-line) AGN-galaxy pairs, and 5.7k Type-2 AGN-galaxy pairs with spec-z studied, with projected distance of 350 kpc. Morphologies of AGN host galaxies derived from Galaxy Zoo project. Results suggest that broad-line AGN and narrow-line AGN reside in widely different environemnts where the neighbors to type-2s are more star forming and bluer than Type-1. There is a colour-dependency only detectable in the neighbors with photometric redshifts for the type-2 AGN. The ration between Type-1/Type-2 neighbors to Type-2 AGN decreases steadily at short separations with a statistical significance of 4.5 sigma [ratio of what? color?]. The lack of change in the morphology of the Type-2 AGN hosts having a close companion (contrary to the case of Type-1 AGN hosts) suggests that the innate state of Type-2 AGN is extremely short-lived and is not preserved in subsequent mergers. Finally, preform a hypothetical luminosity test to investigate whether a mass bias in our selection could explain the observed differences in the samples. Conclusion: AGN unification is consistently not supported by the environment of the two types of AGN, but that an evolutionary connection between them might exist.
1211.0532
Toward more realistic forecasting of dark energy constraints from galaxy redshift surveys
Want, Chuang, Hirata
Improve forecasting of DE constraints from galaxy z surveys by using the "dewiggled" galaxy power spectrum, P_dw(k), in the Fisher matrix calculations; it is a good fit to real galaxy clustering data over most of the scale range of interest. Find: new approach gives results in excellent agreement when compared to the results from the actual data analysis of the clustering of SDSS DR7 LRGs. Forecasts for stage IV surveys.
1211.0536
Dwarf galaxies and the Cosmic web
Benitez-Llambay, Navarro, et al
Use cosmological simulation of the formation of local group of galaxies to identify a mechanism that enables the removal of baryons from low-mass haloes without appealing to feedback or reionization. As the LG forms, matter bound to it forms a network of filaments and pancakes. This moving web of gas and DM drifts and sweeps a large volume, overtaking many haloes in the process. The DM content of these haloes is unaffected byt their gas can be efficiently removed by ram-pressure. The loss of gas is especially pronounced in low-mass haloes due to their lower binding energy, and has a dramatic effect on the SFH of affected systems. This "cosmic web stripping" may help to explain the scarcity of dwarf galaxies compared with the numerous low-mass haloes expected in LCDM and the large diversity of SFH and morphologies characteristic of faint galaxies. Although results are based on a single high-res sim, it is likely that the hydro interaction of dwarf galaxies with the cosmic web is a crucial ingredient so far missing from galaxy formation models.
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