Julianne J. Dalcanton

University of Washington Seattle, Seattle, WA, United States

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Publications (291)1006.4 Total impact

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    ABSTRACT: The duration of a starburst is a fundamental parameter affecting the evolution of galaxies yet, to date, observational constraints on the durations of starbursts are not well established. Here we study the recent star formation histories of three nearby dwarf galaxies to rigorously quantify the duration of their starburst events using a uniform and consistent approach. We find that the bursts range from ∼200 to ∼400 Myr in duration resolving the tension between the shorter timescales often derived observationally with the longer timescales derived from dynamical arguments. If these three starbursts are typical of starbursts in dwarf galaxies, then the short timescales (3–10 Myr) associated with starbursts in previous studies are best understood as "flickering" events which are simply small components of the larger starburst. In this sample of three nearby dwarfs, the bursts are not localized events. All three systems show bursting levels of star formation in regions of both high and low stellar density. The enhanced star formation moves around the galaxy during the bursts and covers a large fraction of the area of the galaxy. These massive, long-duration bursts can significantly affect the structure, dynamics, and chemical evolution of the host galaxy and can be the progenitors of "superwinds" that drive much of the recently chemically enriched material from the galaxy into the intergalactic medium.
    The Astrophysical Journal 10/2015; 695(1):561-573. DOI:10.1088/0004-637X/695/1/561 · 6.28 Impact Factor
  • Proceedings of the International Astronomical Union 07/2015; 10(S309):57-60. DOI:10.1017/S1743921314009302
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    ABSTRACT: Using Hubble Space Telescope Advanced Camera for Surveys (HST/ACS) and Wide Field Camera 3 (WFC3) observations from the Panchromatic Hubble Andromeda Treasury (PHAT), we present new period-luminosity relations for Cepheid variables in M31. Cepheid from several ground-based studies are identified in the PHAT pho- tometry to derive new Period-Luminosity and Wesenheit Period-Luminosity relations in the NIR and visual filters. We derive a distance modulus to M31 of 24.51+/-0.08 in the IR bands and 24.32+/-0.09 in the visual bands, including the first PL relations in the F475W and F814W filters for M31. Our derived visual and IR distance moduli dis- agree at slightly more than a 1-{\sigma} level. Differences in the Period-Luminosity relations between ground-based and HST observations are investigated for a subset of Cepheids. We find a significant discrepancy between ground-based and HST Period-Luminosity relations with the same Cepheids, suggesting adverse effects from photometric contam- ination in ground-based Cepheid observations. Additionally, a statistically significant radial trend in the PL relation is found which does not appear to be explained by metallicity.
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    ABSTRACT: We measure the recent star formation history (SFH) across M31 using optical images taken with the \texit{Hubble Space Telescope} as part of the Panchromatic Hubble Andromeda Treasury (PHAT). We fit the color-magnitude diagrams in ~9000 regions that are ~100 pc $\times$ 100 pc in projected size, covering a 0.5 square degree area (~380 kpc$^2$, deprojected) in the NE quadrant of M31. We show that the SFHs vary significantly on these small spatial scales but that there are also coherent galaxy-wide fluctuations in the SFH back to ~500 Myr, most notably in M31's 10-kpc star-forming ring. We find that the 10-kpc ring is at least 400 Myr old, showing ongoing star formation over the past ~500 Myr. This indicates the presence of molecular gas in the ring over at least 2 dynamical times at this radius. We also find that the ring's position is constant throughout this time, and is stationary at the level of 1 km/s, although there is evidence for broadening of the ring due to diffusion of stars into the disk. Based on existing models of M31's ring features, the lack of evolution in the ring's position makes a purely collisional ring origin highly unlikely. We find that the global SFR has been fairly constant over the last ~500 Myr, though it does show a small increase at 50 Myr that is 1.3 times the average SFR over the past 100 Myr. During the last ~500 Myr, ~60% of all SF occurs in the 10-kpc ring. Finally, we find that in the past 100 Myr, the average SFR over the PHAT survey area is $0.28\pm0.03$ M$_\odot$ yr$^{-1}$ with an average deprojected intensity of $7.3 \times 10^{-4}$ M$_\odot$ yr$^{-1}$ kpc$^{-2}$, which yields a total SFR of ~0.7 M$_\odot$ yr$^{-1}$ when extrapolated to the entire area of M31's disk. This SFR is consistent with measurements from broadband estimates. [abridged]
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    ABSTRACT: We have identified a major global enhancement of star formation in the inner M31 disk that occurred between 2-4 Gyr ago, producing $\sim$60% of the stellar mass formed in the past 5 Gyr. The presence of this episode in the inner disk was discovered by modeling the optical resolved star color-magnitude diagrams of low extinction regions in the main disk of M31 (3$<$R$<$20 kpc) as part of the Panchromatic Hubble Andromeda Treasury. This measurement confirms and extends recent measurements of a widespread star formation enhancement of similar age in the outer disk, suggesting that this burst was both massive and global. Following the galaxy-wide burst, the star formation rate of M31 has significantly declined. We briefly discuss possible causes for these features of the M31 evolutionary history, including interactions with M32, M33 and/or a merger.
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    ABSTRACT: We explore the quenching of low-mass galaxies (10^4 < Mstar < 10^8 Msun) as a function of lookback time using the star formation histories (SFHs) of 38 Local Group dwarf galaxies. The SFHs were derived from analyzing color-magnitude diagrams of resolved stellar populations in archival Hubble Space Telescope/Wide Field Planetary Camera 2 imaging. We find: (1) Lower mass galaxies quench earlier than higher mass galaxies; (2) Inside of virial radius there is no correlation between a satellite's current proximity to a massive host and its quenching epoch; (3) There are hints of systematic differences in quenching times of M31 and Milky Way (MW) satellites, although the sample sample size and uncertainties in the SFHs of M31 dwarfs prohibit definitive conclusions. Combined with literature results, we qualitatively consider the redshift evolution (z=0-1) of the quenched galaxy fraction over ~7 dex in stellar mass (10^4 < Mstar < 10^11.5 Msun). The quenched fraction of all galaxies generally increases toward the present, with both the lowest and highest mass systems exhibiting the largest quenched fractions at all redshifts. In contrast, galaxies between Mstar ~ 10^8-10^10 Msun have the lowest quenched fractions. We suggest that such intermediate-mass galaxies are the least efficient at quenching. Finally, we compare our quenching times with predictions for infall times of low-mass galaxies associated with the MW. We find that some of the lowest-mass satellites (e.g., CVn II, Leo IV) may have been quenched before infall while higher mass satellites (e.g., Leo I, Fornax) typically quench ~1-4 Gyr after infall.
    The Astrophysical Journal 03/2015; 804(2). DOI:10.1088/0004-637X/804/2/136 · 6.28 Impact Factor
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    ABSTRACT: We have undertaken the largest systematic study of the high-mass stellar initial mass function (IMF) to date using the optical color-magnitude diagrams (CMDs) of 85 resolved, young (4 Myr < t < 25 Myr), intermediate mass star clusters (10^3-10^4 Msun), observed as part of the Panchromatic Hubble Andromeda Treasury (PHAT) program. We fit each cluster's CMD to measure its mass function (MF) slope for stars >2 Msun. For the ensemble of clusters, the distribution of stellar MF slopes is best described by $\Gamma=+1.45^{+0.03}_{-0.06}$ with a very small intrinsic scatter. The data also imply no significant dependencies of the MF slope on cluster age, mass, and size, providing direct observational evidence that the measured MF represents the IMF. This analysis implies that the high-mass IMF slope in M31 clusters is universal with a slope ($\Gamma=+1.45^{+0.03}_{-0.06}$) that is steeper than the canonical Kroupa (+1.30) and Salpeter (+1.35) values. Using our inference model on select Milky Way (MW) and LMC high-mass IMF studies from the literature, we find $\Gamma_{\rm MW} \sim+1.15\pm0.1$ and $\Gamma_{\rm LMC} \sim+1.3\pm0.1$, both with intrinsic scatter of ~0.3-0.4 dex. Thus, while the high-mass IMF in the Local Group may be universal, systematics in literature IMF studies preclude any definitive conclusions; homogenous investigations of the high-mass IMF in the local universe are needed to overcome this limitation. Consequently, the present study represents the most robust measurement of the high-mass IMF slope to date. We have grafted the M31 high-mass IMF slope onto widely used sub-solar mass Kroupa and Chabrier IMFs and show that commonly used UV- and Halpha-based star formation rates should be increased by a factor of ~1.3-1.5 and the number of stars with masses >8 Msun are ~25% fewer than expected for a Salpeter/Kroupa IMF. [abridged]
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    ABSTRACT: The stellar kinematics of galactic disks are key to constraining disk formation and evolution processes. In this paper, for the first time, we measure the stellar age-velocity dispersion correlation in the inner 20 kpc (3.5 disk scale lengths) of M31 and show that it is dramatically different from that in the Milky Way. We use optical Hubble Space Telescope/Advanced Camera for Surveys photometry of 5800 individual stars from the Panchromatic Hubble Andromeda Treasury (PHAT) survey and Keck/DEIMOS radial velocity measurements of the same stars from the Spectroscopic and Photometric Landscape of Andromeda's Stellar Halo (SPLASH) survey. We show that the average line-of-sight velocity dispersion is a steadily increasing function of stellar age exterior to R=10 kpc, increasing from 30 km/s for the young upper main sequence stars to 90 km/s for the old red giant branch stars. This monotonic increase implies that a continuous or recurring process contributed to the evolution of the disk. Both the slope and normalization of the dispersion vs. age relation are significantly larger than in the Milky Way, allowing for the possibility that the disk of M31 has had a more violent history than the disk of the Milky Way, more in line with cosmological predictions. We also find evidence for an inhomogeneous distribution of stars from a second kinematical component in addition to the dominant disk component. One of the largest and hottest high-dispersion patches is present in all age bins, and may be the signature of the end of the long bar.
    The Astrophysical Journal 02/2015; 803(1). DOI:10.1088/0004-637X/803/1/24 · 6.28 Impact Factor
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    ABSTRACT: We have analyzed new HST/ACS and HST/WFC3 imaging in F475W and F814W of two previously-unobserved fields along the M31 minor axis to confirm our previous constraints on the shape of M31's inner stellar halo. Both of these new datasets reach a depth of at least F814W$<$27 and clearly detect the blue horizontal branch (BHB) of the field as a distinct feature of the color-magnitude diagram. We measure the density of BHB stars and the ratio of BHB to red giant branch stars in each field using identical techniques to our previous work. We find excellent agreement with our previous measurement of a power-law for the 2-D projected surface density with an index of 2.6$^{+0.3}_{-0.2}$ outside of 3 kpc, which flattens to $\alpha <$1.2 inside of 3 kpc. Our findings confirm our previous suggestion that the field BHB stars in M31 are part of the halo population. However, the total halo profile is now known to differ from this BHB profile, which suggests that we have isolated the metal-poor component. This component appears to have an unbroken power-law profile from 3-150 kpc but accounts for only about half of the total halo stellar mass. Discrepancies between the BHB density profile and other measurements of the inner halo are therefore likely due to the different profile of the metal-rich halo component, which is not only steeper than the profile of the met al-poor component, but also has a larger core radius. These profile differences also help to explain the large ratio of BHB/RGB stars in our observations.
    The Astrophysical Journal 01/2015; 802(1). DOI:10.1088/0004-637X/802/1/49 · 6.28 Impact Factor
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    ABSTRACT: We construct a stellar cluster catalog for the Panchromatic Hubble Andromeda Treasury (PHAT) survey using image classifications collected from the Andromeda Project citizen science website. We identify 2,753 clusters and 2,270 background galaxies within ~0.5 deg$^2$ of PHAT imaging searched, or ~400 kpc$^2$ in deprojected area at the distance of the Andromeda galaxy (M31). These identifications result from 1.82 million classifications of ~20,000 individual images (totaling ~7 gigapixels) by tens of thousands of volunteers. We show that our crowd-sourced approach, which collects >80 classifications per image, provides a robust, repeatable method of cluster identification. The high spatial resolution Hubble Space Telescope images resolve individual stars in each cluster and are instrumental in the factor of ~6 increase in the number of clusters known within the survey footprint. We measure integrated photometry in six filter passbands, ranging from the near-UV to the near-IR. PHAT clusters span a range of ~8 magnitudes in F475W (g-band) luminosity, equivalent to ~4 decades in cluster mass. We perform catalog completeness analysis using >3000 synthetic cluster simulations to determine robust detection limits and demonstrate that the catalog is 50% complete down to ~500 solar masses for ages <100 Myr. We include catalogs of clusters, background galaxies, remaining unselected candidates, and synthetic cluster simulations, making all information publicly available to the community. The catalog published here serves as the definitive base data product for PHAT cluster science, providing a census of star clusters in an L$^*$ spiral galaxy with unmatched sensitivity and quality.
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    ABSTRACT: The evolution and lifetimes of thermally pulsating asymptotic giant branch (TP-AGB) stars suffer from significant uncertainties. We present a detailed framework for constraining model luminosity functions of TP-AGB stars using resolved stellar populations. We show an example of this method that compares various TP-AGB mass-loss prescriptions that differ in their treatments of mass loss before the onset of dust-driven winds (pre-dust). We find that models with more efficient pre-dust driven mass loss produce results consistent with observations, as opposed to more canonical mass-loss models. Efficient pre-dust driven mass-loss predicts for [Fe/H] < -1.2, lower mass TP-AGB stars (M < 1 Msun) must have lifetimes less than about 1.2 Myr.
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    ABSTRACT: The [CII] 158 micron line is one of the strongest emission lines observed in star-forming galaxies, and has been empirically measured to correlate with the star formation rate (SFR) globally and on ~kpc scales. However, due to the multi-phase origins of [CII], one might expect this relation to break down at small scales. We investigate the origins of [CII] emission by examining high spatial resolution observations of [CII] in M31, with the Survey of Lines in M31 (SLIM). We present five ~700x700 pc (3"x3") Fields mapping the [CII] emission, Halpha emission, combined with ancillary infrared (IR) data. We spatially separate star-forming regions from diffuse gas and dust emission on ~50 pc scales. We find that the [CII] - SFR correlation holds even at these scales, although the relation typically has a flatter slope than found at larger (~kpc) scales. While the Halpha emission in M31 is concentrated in the SFR regions, we find that a significant amount (~20-90%) of the [CII] emission comes from outside star-forming regions, and that the total IR (TIR) emission has the highest diffuse fraction of all SFR tracers. We find a weak correlation of the [CII]/TIR to dust color in each Field, and find a large scale trend of increasing [CII]/TIR with galactocentric radius. The differences in the relative diffuse fractions of [CII], Halpha and IR tracers are likely caused by a combination of energetic photon leakage from HII regions and heating by the diffuse radiation field arising from older (B-star) stellar populations. However, we find that by averaging our measurements over ~kpc scales, these effects are minimized, and the relation between [CII] and SFR found in other nearby galaxy studies is retrieved.
    The Astrophysical Journal 10/2014; 798(1). DOI:10.1088/0004-637X/798/1/24 · 6.28 Impact Factor
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    ABSTRACT: Our proximity and external vantage point make M31 an ideal testbed for understanding the structure of spiral galaxies. The Andromeda Optical and Infrared Disk Survey (ANDROIDS) has mapped M31's bulge and disk out to R=40 kpc in $ugriJK_s$ bands with CFHT using a careful sky calibration. We use Bayesian modelling of the optical-infrared spectral energy distribution (SED) to estimate profiles of M31's stellar populations and mass along the major axis. This analysis provides evidence for inside-out disk formation and a declining metallicity gradient. M31's $i$-band mass-to-light ratio ($M/L_i^*$) decreases from 0.5 dex in the bulge to $\sim 0.2$ dex at 40 kpc. The best-constrained stellar population models use the full $ugriJK_s$ SED but are also consistent with optical-only fits. Therefore, while NIR data can be successfully modelled with modern stellar population synthesis, NIR data do not provide additional constraints in this application. Fits to the $gi$-SED alone yield $M/L_i^*$ that are systematically lower than the full SED fit by 0.1 dex. This is still smaller than the 0.3 dex scatter amongst different relations for $M/L_i$ via $g-i$ colour found in the literature. We advocate a stellar mass of $M_*(30\mathrm{kpc})=10.3^{+2.3}_{-1.7}\times 10^{10}\mathrm{M}_\odot$ for the M31 bulge and disk.
    Proceedings of the International Astronomical Union 09/2014; 10(S311). DOI:10.1017/S1743921315003440
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    ABSTRACT: Using Hubble Space Telescope (HST) photometry to measure star formation histories, we age-date the stellar populations surrounding supernova remnants (SNRs) in M31 and M33. We then apply stellar evolution models to the ages to infer the corresponding masses for their supernova progenitor stars. We analyze 33 M33 SNR progenitors and 29 M31 SNR progenitors in this work. We then combine these measurements with 53 previously published M31 SNR progenitor measurements to bring our total number of progenitor mass estimates to 115. To quantify the mass distributions, we fit power laws of the form $dN/dM \propto M^{-\alpha}$. Our new, larger sample of M31 progenitors follows a distribution with $\alpha = 4.4\pm 0.4$, and the M33 sample follows a distribution with $\alpha = 3.8^{+0.4}_{-0.5}$. Thus both samples are consistent within the uncertainties, and the full sample across both galaxies gives $\alpha = 4.2\pm 0.3$. Both the individual and full distributions display a paucity of massive stars when compared to a Salpeter initial mass function (IMF), which we would expect to observe if all massive stars exploded as SN that leave behind observable SNR. If we instead fix $\alpha = 2.35$ and treat the maximum mass as a free parameter, we find $M_{max} \sim 35-45M_{sun}$, indicative of a potential maximum cutoff mass for SN production. Our results suggest that either SNR surveys are biased against finding objects in the youngest (<10 Myr old) regions, or the highest mass stars do not produce SNe.
    The Astrophysical Journal 09/2014; 795(2). DOI:10.1088/0004-637X/795/2/170 · 6.28 Impact Factor
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    ABSTRACT: We have measured stellar photometry with the Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) and Advanced Camera for Surveys (ACS) in near ultraviolet (F275W, F336W), optical (F475W, F814W), and near infrared (F110W, F160W) bands for 117 million resolved stars in M31. As part of the Panchromatic Hubble Andromeda Treasury (PHAT) survey, we measured photometry with simultaneous point spread function fitting across all bands and at all source positions after precise astrometric image alignment (<5-10 milliarcsecond accuracy). In the outer disk, the photometry reaches a completeness-limited depth of F475W~28, while in the crowded, high surface brightness bulge, the photometry reaches F475W~25. We find that simultaneous photometry and optimized measurement parameters significantly increase the detection limit of the lowest resolution filters (WFC3/IR) providing color-magnitude diagrams that are up to 2.5 magnitudes deeper when compared with color-magnitude diagrams from WFC3/IR photometry alone. We present extensive analysis of the data quality including comparisons of luminosity functions and repeat measurements, and we use artificial star tests to quantify photometric completeness, uncertainties and biases. We find that largest sources of systematic error in the photometry are due to spatial variations in the point spread function models and charge transfer efficiency corrections. This stellar catalog is the largest ever produced for equidistant sources, and is publicly available for download by the community.
    The Astrophysical Journal Supplement Series 09/2014; 215(1). DOI:10.1088/0067-0049/215/1/9 · 14.14 Impact Factor
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    ABSTRACT: We search Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) and Wide Field Camera 3 (WFC3) broadband imaging data from the Panchromatic Hubble Andromeda Treasury (PHAT) survey to identify detections of cataloged planetary nebulae (PNe). Of the 711 PNe currently in the literature within the PHAT footprint, we find 467 detected in the broadband. For these 467 we are able to refine their astrometric accuracy from ~0."3 to 0."05. Using the resolution of HST, we are able to show that 152 objects currently in the catalogs are definitively not PNe, and we show that 32 objects thought to be extended in ground-based images are actually point-like and therefore good PN candidates. We also find one PN candidate that is marginally resolved. If this is a PN, it is up to 0.7 pc in diameter. With our new photometric data, we develop a method of measuring the level of excitation in individual PNe by comparing broadband and narrowband imaging and describe the effects of excitation on a PN's photometric signature. Using the photometric properties of the known PNe in the PHAT catalogs, we search for more PN, but do not find any new candidates, suggesting that ground-based emission-line surveys are complete in the PHAT footprint to F475W $\simeq$ 24.
    The Astrophysical Journal 07/2014; 792(2). DOI:10.1088/0004-637X/792/2/121 · 6.28 Impact Factor
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    ABSTRACT: We investigate the clustering of early-type stars younger than 300 Myr on galactic scales in M31. Based on the stellar photometric catalogs of the Panchromatic Hubble Andromeda Treasury program that also provides stellar parameters derived from the individual energy distributions, our analysis is focused on the young stars in three star-forming regions, located at galactocentric distances of about 5, 10, and 15 kpc, corresponding to the inner spiral arms, the ring structure, and the outer arm, respectively. We apply the two-point correlation function to our selected sample to investigate the clustering behavior of these stars across different time- and length-scales. We find that young stellar structure survives across the whole extent of M31 longer than 300 Myr. Stellar distribution in all regions appears to be self-similar, with younger stars being systematically more strongly clustered than the older, which are more dispersed. The observed clustering is interpreted as being induced by turbulence, the driving source for which is probably gravitational instabilities driven by the spiral arms, which are stronger closer to the galactic centre.
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    ABSTRACT: We present results from new near-infrared (NIR) imaging from the Spitzer Space Telescope that trace the low surface brightness features of the outer disk and stellar stream in the nearby spiral galaxy, M83. Previous observations have shown that M83 hosts a faint stellar stream to the northwest and a star-forming disk that extends to ~3 times the optical radius (R 25). By combining the NIR imaging with archival far-ultraviolet (FUV) and H I imaging, we study the star formation history of the system. The NIR surface brightness profile has a break at ~5.'8 (equivalent to 8.1 kpc and 0.9 R 25) with a shallower slope beyond this radius, which may result from the recent accretion of gas onto the outer disk and subsequent star formation. Additionally, the ratio of FUV to NIR flux increases with increasing radius in several arms throughout the extended star forming disk, indicating an increase in the ratio of the present to past star formation rate with increasing radius. This sort of inside-out disk formation is consistent with observations of gas infall onto the outer disk of M83. Finally, the flux, size, and shape of the stellar stream are measured and the origin of the stream is explored. The stream has a total NIR flux of 11.6 mJy, which implies a stellar mass of 1 × 108M ☉ in an area subtending ~80°. No FUV emission is detected in the stream at a level greater than the noise, confirming an intermediate-age or old stellar population in the stream.
    The Astrophysical Journal 06/2014; 789(2):126. DOI:10.1088/0004-637X/789/2/126 · 6.28 Impact Factor
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    ABSTRACT: The evolution and lifetimes of thermally pulsating asymptotic giant branch (TP-AGB) stars suffer from significant uncertainties. In this work, we analyze the numbers and luminosity functions of TP-AGB stars in six quiescent, low metallicity ([Fe/H] $\lesssim -0.86$) galaxies taken from the ANGST sample, using HST photometry in both optical and near-infrared filters. The galaxies contain over 1000 TP-AGB stars (at least 60 per field). We compare the observed TP-AGB luminosity functions and relative numbers of TP-AGB and RGB stars, to models generated from different suites of TP-AGB evolutionary tracks after adopting star formation histories (SFH) derived from the HST deep optical observations. We test various mass-loss prescriptions that differ in their treatments of mass-loss before the onset of dust-driven winds (pre-dust). These comparisons confirm that pre-dust mass-loss is important, since models that neglect pre-dust mass-loss fail to explain the observed TP-AGB/RGB ratio or the luminosity functions. In contrast, models with more efficient pre-dust mass-loss produce results consistent with observations. We find that for [Fe/H]$\lesssim-0.86$, lower mass TP-AGB stars ($M\lesssim1M_\odot$) must have lifetimes of $\sim0.5$ Myr and higher masses ($M\lesssim 3M_\odot$) must have lifetimes $\lesssim 1.2$ Myr. In addition, assuming our best-fitting mass-loss prescription, we show that the third dredge up has no significant effect on TP-AGB lifetimes in this mass and metallicity range.
    The Astrophysical Journal 06/2014; 790(1). DOI:10.1088/0004-637X/790/1/22 · 6.28 Impact Factor
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    ABSTRACT: Using resolved stellar photometry measured from archival HST imaging, we generate color-magnitude diagrams of the stars within 50 pc of the locations of historic core-collapse supernovae that took place in galaxies within 8 Mpc. We fit these color-magnitude distributions with stellar evolution models to determine the best-fit age distribution of the young population. We then translate these age distributions into probability distributions for the progenitor mass of each SNe. The measurements are anchored by the main-sequence stars surrounding the event, making them less sensitive to assumptions about binarity, post-main-sequence evolution, or circumstellar dust. We demonstrate that, in cases where the literature contains masses that have been measured from direct imaging, our measurements are consistent with (but less precise than) these measurements. Using this technique, we constrain the progenitor masses of 17 historic SNe, 11 of which have no previous estimates from direct imaging. Our measurements still allow the possibility that all SNe progenitor masses are <20 M_sun. However, the large uncertainties for the highest-mass progenitors also allow the possibility of no upper-mass cutoff.
    The Astrophysical Journal 05/2014; 791(2). DOI:10.1088/0004-637X/791/2/105 · 6.28 Impact Factor

Publication Stats

8k Citations
1,006.40 Total Impact Points

Institutions

  • 1999–2015
    • University of Washington Seattle
      • Department of Astronomy
      Seattle, WA, United States
  • 2014
    • The Astronomical Observatory of Brera
      Merate, Lombardy, Italy
  • 2008–2014
    • Space Telescope Science Institute
      Baltimore, Maryland, United States
  • 2012
    • Leibniz Institute for Astrophysics Potsdam
      Potsdam, Brandenburg, Germany
  • 2001–2010
    • The University of Arizona
      • Department of Astronomy
      Tucson, Arizona, United States
  • 2009
    • University of California, Berkeley
      • Department of Astronomy
      Berkeley, CA, United States
  • 1996–2009
    • Carnegie Institution for Science
      Washington, West Virginia, United States
    • Carnegie Institute
      Pasadena, Texas, United States
  • 2007
    • University of Chicago
      • Department of Astronomy and Astrophysics
      Chicago, Illinois, United States
  • 2006
    • Johns Hopkins University
      • Department of Physics and Astronomy
      Baltimore, Maryland, United States
  • 2005
    • University of Nottingham
      • School of Physics and Astronomy
      Nottigham, England, United Kingdom
  • 2003
    • Eötvös Loránd University
      • Department of Physics of Complex Systems
      Budapeŝto, Budapest, Hungary
  • 2002
    • Fermi National Accelerator Laboratory (Fermilab)
      Batavia, Illinois, United States
  • 2000
    • University of California, Santa Cruz
      • Department of Astronomy and Astrophysics
      Santa Cruz, California, United States