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1,439 results on '"Hale, D."'

1. ZTF SN Ia DR2: Evidence of Changing Dust Distributions With Redshift Using Type Ia Supernovae

Author

Popovic, B., Rigault, M., Smith, M., Ginolin, M., Goobar, A., Kenworthy, W. D., Ganot, C., Ruppin, F., Dimitriadis, G., Johansson, J., Amenouche, M., Aubert, M., Barjou-Delayre, C., Burgaz, U., Carreres, B., Feinstein, F., Fouchez, D., Galbany, L., de Jaeger, T., Kim, Y. -L., Lacroix, L., Nugent, P. E., Racine, B., Rosselli, D., Rosnet, P., Sollerman, J., Hale, D., Laher, R., Müller-Bravo, T. E., Reed, R., Rusholme, B., and Terwel, J.

Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - Astrophysics of Galaxies
Abstract

Type Ia supernova (SNIa) are excellent probes of local distance, and the increasing sample sizes of SNIa have driven an increased need to study the associated systematic uncertainties and improve the standardisation methods in preparation for the next generation of cosmological surveys into the dark energy equation-of-state $w$. We aim to probe the potential change in the SNIa standardisation parameter $c$ with redshift and the host-galaxy of the supernova. Improving the standardisation of SNIa brightnesses will require accounting for the relationship between the host and the SNIa, and potential shifts in the SNIa standardisation parameters with redshift will cause biases in the recovered cosmology. Here, we assemble a volume-limited sample of ~3000 likely SNIa across a redshift range of $z = 0.015$ to $z = 0.36$. This sample is fitted with changing mass and redshift bins to determine the relationship between intrinsic properties of SNe Ia and their redshift and host galaxy parameters. We then investigate the colour-luminosity parameter $\beta$ as a further test of the SNIa standardisation process. We find that the changing colour distribution of SNe Ia with redshift is driven by dust at a confidence of $>4\sigma$. Additionally, we show a strong correlation between the host galaxy mass and the colour-luminosity coefficient $\beta$ ($> 4\sigma$), even when accounting for the quantity of dust in a host galaxy.

Published
2024

2. Supernova Siblings and their Parent Galaxies in the Zwicky Transient Facility Bright Transient Surve

Author

Graham, M. L., Fremling, C., Perley, D. A., Biswas, R., Phillips, C. A., Sollerman, J., Nugent, P. E., Nance, S., Dhawan, S., Nordin, J., Goobar, A., Miller, A., Neill, J. D., Hall, X. J., Hankins, M. J., Duev, D. A., Kasliwal, M. M., Rigault, M., Bellm, E. C., Hale, D., Mróz, P., and Kulkarni, S. R.

Subjects
Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Astrophysics of Galaxies
Abstract

Supernova (SN) siblings -- two or more SNe in the same parent galaxy -- are useful tools for exploring progenitor stellar populations as well as properties of the host galaxies such as distance, star formation rate, dust extinction, and metallicity. Since the average SN rate for a Milky Way-type galaxy is just one per century, a large imaging survey is required to discover an appreciable sample of SN siblings. From the wide-field Zwicky Transient Facility (ZTF) Bright Transient Survey (BTS; which aims for spectroscopic completeness for all transients which peak brighter than $r{<}$18.5 mag) we present 10 SN siblings in 5 parent galaxies. For each of these families we analyze the SN's location within the host and its underlying stellar population, finding agreement with expectations that SNe from more massive progenitors are found nearer to their host core and in regions of more active star formation. We also present an analysis of the relative rates of core collapse and thermonuclear SN siblings, finding a significantly lower ratio than past SN sibling samples due to the unbiased nature of the ZTF., Comment: 14 pages, 4 tables, 7 figures, accepted to MNRAS

Published
2021
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3. SN2020bvc: a Broad-lined Type Ic Supernova with a Double-peaked Optical Light Curve and a Luminous X-ray and Radio Counterpart

Author

Ho, A. Y. Q., Kulkarni, S. R., Perley, D. A., Cenko, S. B., Corsi, A., Schulze, S., Lunnan, R., Sollerman, J., Gal-Yam, A., Anand, S., Barbarino, C., Bellm, E., Bruch, R., Burns, E., De, K., Dekany, R., Delacroix, A., Duev, D., Fremling, C., Goldstein, D., Golkhou, Z., Graham, M. J., Hale, D., Kasliwal, M. M., Kupfer, T., Laher, R., Martikainen, J., Masci, F. J., Neill, J. D., Rusholme, B., Shupe, D. L., Soumagnac, M. T., Strotjohann, N. L., Taggart, K., Tartaglia, L., Yan, L., and Zolkower, J.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

We present optical, radio, and X-ray observations of SN2020bvc (=ASASSN20bs; ZTF20aalxlis), a nearby ($z=0.0252$; $d$=114 Mpc) broad-lined (BL) Type Ic supernova (SN). Our observations show that SN2020bvc shares several properties in common with the Ic-BL SN2006aj, which was associated with the low-luminosity gamma-ray burst (LLGRB) 060218. First, the 10 GHz radio light curve is on the faint end of LLGRB-SNe ($L_\mathrm{radio} \approx 10^{37}$erg/s): we model our VLA observations (spanning 13-43 d) as synchrotron emission from a mildly relativistic ($v \gtrsim 0.3c$) forward shock. Second, with Swift and Chandra we detect X-ray emission ($L_X \approx 10^{41}$erg/s) that is not naturally explained as inverse Compton emission or as part of the same synchrotron spectrum as the radio emission. Third, high-cadence ($6\times$/night) data from the Zwicky Transient Facility (ZTF) shows a double-peaked optical light curve, the first peak from shock-cooling emission from extended low-mass material (mass $M<10^{-2} M_\odot$ at radius $R>10^{12}$cm) and the second peak from the radioactive decay of Ni-56. SN2020bvc is the first confirmed double-peaked Ic-BL SN discovered without a GRB trigger, and shows X-ray and radio emission similar to LLGRB-SNe: this is consistent with models in which the same mechanism produces both the LLGRB and the shock-cooling emission. For four of the five other nearby ($z\lesssim0.05$) Ic-BL SNe with ZTF high-cadence data, we rule out a first peak like that seen in SN2006aj and SN2020bvc, i.e. that lasts $\approx 1$d and reaches a peak luminosity $M \approx -18$. X-ray and radio follow-up observations of future such events will establish whether double-peaked optical light curves are indeed predictive of LLGRB-like X-ray and radio emission., Comment: Accepted to ApJ. 39 pages, 17 figures. Comments welcome

Published
2020
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4. The Koala: A Fast Blue Optical Transient with Luminous Radio Emission from a Starburst Dwarf Galaxy at $z=0.27$

Author

Ho, Anna Y. Q., Perley, D. A., Kulkarni, S. R., Dong, D. Z. J., De, K., Chandra, P., Andreoni, I., Bellm, E. C., Burdge, K. B., Coughlin, M., Dekany, R., Feeney, M., Frederiks, D. D., Fremling, C., Golkhou, V. Z., Graham, M., Hale, D., Helou, G., Horesh, A., Laher, R. R., Masci, F., Miller, A. A., Porter, M., Ridnaia, A., Rusholme, B., Shupe, D. L., Soumagnac, M. T., and Svinkin, D. S.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

We present ZTF18abvkwla (the "Koala"), a fast blue optical transient discovered in the Zwicky Transient Facility (ZTF) One-Day Cadence (1DC) Survey. ZTF18abvkwla has a number of features in common with the groundbreaking transient AT2018cow: blue colors at peak ($g-r\approx-0.5$ mag), a short rise time from half-max of under two days, a decay time to half-max of only three days, a high optical luminosity ($M_{g,\mathrm{peak}}\approx-20.6$mag), a hot ($\gtrsim 40,000$K) featureless spectrum at peak light, and a luminous radio counterpart. At late times ($\Delta t>80$d) the radio luminosity of ZTF18abvkwla ($\nu L_\nu \gtrsim 10^{40}$erg/s at 10 GHz, observer-frame) is most similar to that of long-duration gamma-ray bursts (GRBs). The host galaxy is a dwarf starburst galaxy ($M\approx5\times10^{8}M_\odot$, $\mathrm{SFR}\approx7 M_\odot$/yr) that is moderately metal-enriched ($\log\mathrm{[O/H]} \approx 8.5$), similar to the hosts of GRBs and superluminous supernovae. As in AT2018cow, the radio and optical emission in ZTF18abvkwla likely arise from two separate components: the radio from fast-moving ejecta ($\Gamma \beta c >0.38c$) and the optical from shock-interaction with confined dense material ($<0.07M_\odot$ in $\sim 10^{15}$cm). Compiling transients in the literature with $t_\mathrm{rise} <5$d and $M_\mathrm{peak}<-20$mag, we find that a significant number are engine-powered, and suggest that the high peak optical luminosity is directly related to the presence of this engine. From 18 months of the 1DC survey, we find that transients in this rise-luminosity phase space are at least two to three orders of magnitude less common than CC SNe. Finally, we discuss strategies for identifying such events with future facilities like the Large Synoptic Survey Telescope, and prospects for detecting accompanying X-ray and radio emission., Comment: 27 pages, 11 figures. Resubmitted to ApJ on 13 April following comments by referee. Comments welcome!

Published
2020
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5. Evidence for Late-stage Eruptive Mass Loss in the Progenitor to SN2018gep, a Broad-lined Ic Supernova: Pre-explosion Emission and a Rapidly Rising Luminous Transient

Author

Ho, AYQ, Goldstein, DA, Schulze, S, Khatami, DK, Perley, DA, Ergon, M, Gal-Yam, A, Corsi, A, Andreoni, I, Barbarino, C, Bellm, EC, Blagorodnova, N, Bright, JS, Burns, E, Cenko, SB, Cunningham, V, De, K, Dekany, R, Dugas, A, Fender, RP, Fransson, C, Fremling, C, Goldstein, A, Graham, MJ, Hale, D, Horesh, A, Hung, T, Kasliwal, MM, M. Kuin, NP, Kulkarni, SR, Kupfer, T, Lunnan, R, Masci, FJ, Ngeow, CC, Nugent, PE, Ofek, EO, Patterson, MT, Petitpas, G, Rusholme, B, Sai, H, Sfaradi, I, Shupe, DL, Sollerman, J, Soumagnac, MT, Tachibana, Y, Taddia, F, Walters, R, Wang, X, Yao, Y, and Zhang, X

Subjects
methods: observational, shock waves, stars: mass-loss, supernovae: individual, surveys, astro-ph.HE, Astronomy & Astrophysics, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Physical Chemistry, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Physical Chemistry (incl. Structural)
Abstract

We present detailed observations of ZTF18abukavn (SN2018gep), discovered in high-cadence data from the Zwicky Transient Facility as a rapidly rising (1.4 ± 0.1 mag hr-1) and luminous (Mg,peak = -20 mag) transient. It is spectroscopically classified as a broad-lined stripped-envelope supernova (Ic-BL SN). The high peak luminosity (Lbol ≳ 3 × 1044 erg s-1), the short rise time (trise = 3 days in g band), and the blue colors at peak (g-r ∼ -0.4) all resemble the high-redshift Ic-BL iPTF16asu, as well as several other unclassified fast transients. The early discovery of SN2018gep (within an hour of shock breakout) enabled an intensive spectroscopic campaign, including the highest-temperature (Teff ≳ 40,000 K) spectra of a stripped-envelope SN. A retrospective search revealed luminous (Mg ∼ Mr ≈ mag) emission in the days to weeks before explosion, the first definitive detection of precursor emission for a Ic-BL. We find a limit on the isotropic gamma-ray energy release E γ,iso < 4.9 × 10 48 erg, a limit on X-ray emission LX < 1040 erg s-1, and a limit on radio emission ν Lν ≲ 1037 erg s-1. Taken together, we find that the early (< 10 days) data are best explained by shock breakout in a massive shell of dense circumstellar material (0.02 M⊙) at large radii (3 × 1014 cm) that was ejected in eruptive pre-explosion mass-loss episodes. The late-time (> 10 days) light curve requires an additional energy source, which could be the radioactive decay of Ni-56.

Published
2019

6. Discovery of an Intermediate-luminosity Red Transient in M51 and Its Likely Dust-obscured, Infrared-variable Progenitor

Author

Jencson, JE, Adams, SM, Bond, HE, Van Dyk, SD, Kasliwal, MM, Bally, J, Blagorodnova, N, De, K, Fremling, C, Yao, Y, Fruchter, A, Rubin, D, Barbarino, C, Sollerman, J, Miller, AA, Hicks, EKS, Malkan, MA, Andreoni, I, Bellm, EC, Buchheim, R, Dekany, R, Feeney, M, Frederick, S, Gal-Yam, A, Gehrz, RD, Giomi, M, Graham, MJ, Green, W, Hale, D, Hankins, MJ, Hanson, M, Helou, G, Ho, AYQ, Hung, T, Jurić, M, Kendurkar, MR, Kulkarni, SR, Lau, RM, Masci, FJ, Neill, JD, Quin, K, Riddle, RL, Rusholme, B, Sims, F, Smith, N, Smith, RM, Soumagnac, MT, Tachibana, Y, Tinyanont, S, Walters, R, Watson, S, and Williams, RE

Subjects
circumstellar matter, galaxies: individual, stars: evolution, stars: variables: general, stars: winds, outflows, supernovae: individual, astro-ph.SR, stars: winds, outflows, Astronomy & Astrophysics, Astronomical and Space Sciences
Abstract

We present the discovery of an optical transient (OT) in Messier 51, designated M51 OT2019-1 (also ZTF 19aadyppr, AT 2019abn, ATLAS19bzl), by the Zwicky Transient Facility (ZTF). The OT rose over 15 days to an observed luminosity of Mr = -13 (νLν = 9 × 106 Lo), in the luminosity gap between novae and typical supernovae (SNe). Spectra during the outburst show a red continuum, Balmer emission with a velocity width of ≈400 km s-1, Ca ii and [Ca ii] emission, and absorption features characteristic of an F-type supergiant. The spectra and multiband light curves are similar to the so-called "SN impostors" and intermediate-luminosity red transients (ILRTs). We directly identify the likely progenitor in archival Spitzer Space Telescope imaging with a 4.5 μm luminosity of M[4.5] ≈ -12.2 mag and a [3.6]-[4.5] color redder than 0.74 mag, similar to those of the prototype ILRTs SN 2008S and NGC 300 OT2008-1. Intensive monitoring of M51 with Spitzer further reveals evidence for variability of the progenitor candidate at [4.5] in the years before the OT. The progenitor is not detected in pre-outburst Hubble Space Telescope optical and near-IR images. The optical colors during outburst combined with spectroscopic temperature constraints imply a higher reddening of E(B - V) ≈ 0.7 mag and higher intrinsic luminosity of Mr ≈ -14.9 mag (νLν = 5.3 × 107 Lo) near peak than seen in previous ILRT candidates. Moreover, the extinction estimate is higher on the rise than on the plateau, suggestive of an extended phase of circumstellar dust destruction. These results, enabled by the early discovery of M51 OT2019-1 and extensive pre-outburst archival coverage, offer new clues about the debated origins of ILRTs and may challenge the hypothesis that they arise from the electron-capture induced collapse of extreme asymptotic giant branch stars.

Published
2019

7. The zwicky transient facility: Science objectives

Author

Graham, MJ, Kulkarni, SR, Bellm, EC, Adams, SM, Barbarino, C, Blagorodnova, N, Bodewits, D, Bolin, B, Brady, PR, Cenko, SB, Chang, CK, Coughlin, MW, Kishalay De, K, Eadie, G, Farnham, TL, Feindt, U, Franckowiak, A, Fremling, C, Gezari, S, Ghosh, S, Goldstein, DA, Golkhou, VZ, Goobar, A, Ho, AYQ, Huppenkothen, D, Ivezić, Ž, Jones, RL, Juric, M, Kaplan, DL, Kasliwal, MM, Kelley, MSP, Kupfer, T, Lee, CD, Lin, HW, Lunnan, R, Mahabal, AA, Miller, AA, Ngeow, CC, Nugent, P, Ofek, EO, Prince, TA, Rauch, L, Van Roestel, J, Schulze, S, Singer, LP, Sollerman, J, Taddia, F, Yan, L, Ye, QZ, Yu, PC, Barlow, T, Bauer, J, Beck, R, Belicki, J, Biswas, R, Brinnel, V, Brooke, T, Bue, B, Bulla, M, Burruss, R, Connolly, A, Cromer, J, Cunningham, V, Dekany, R, Delacroix, A, Desai, V, Duev, DA, Feeney, M, Flynn, D, Frederick, S, Gal-Yam, A, Giomi, M, Groom, S, Hacopians, E, Hale, D, Helou, G, Henning, J, Hover, D, Hillenbrand, LA, Howell, J, Hung, T, Imel, D, Ip, WH, Jackson, E, Kaspi, S, Kaye, S, Kowalski, M, Kramer, E, Kuhn, M, Landry, W, Laher, RR, Mao, P, Masci, FJ, Monkewitz, S, Murphy, P, Nordin, J, Patterson, MT, Penprase, B, Porter, M, and Rebbapragada, U

Subjects
(stars:) supernovae: general, surveys, (galaxies:) quasars: general, astro-ph.IM, astro-ph.HE, Astronomy & Astrophysics, Astronomical and Space Sciences
Abstract

The Zwicky Transient Facility (ZTF), a public–private enterprise, is a new time-domain survey employing a dedicated camera on the Palomar 48-inch Schmidt telescope with a 47 deg2 field of view and an 8 second readout time. It is well positioned in the development of time-domain astronomy, offering operations at 10% of the scale and style of the Large Synoptic Survey Telescope (LSST) with a single 1-m class survey telescope. The public surveys will cover the observable northern sky every three nights in g and r filters and the visible Galactic plane every night in g and r. Alerts generated by these surveys are sent in real time to brokers. A consortium of universities that provided funding (“partnership”) are undertaking several boutique surveys. The combination of these surveys producing one million alerts per night allows for exploration of transient and variable astrophysical phenomena brighter than r∼20.5 on timescales of minutes to years. We describe the primary science objectives driving ZTF, including the physics of supernovae and relativistic explosions, multi-messenger astrophysics, supernova cosmology, active galactic nuclei, and tidal disruption events, stellar variability, and solar system objects.

Published
2019

8. ZTF 18aaqeasu (SN2018byg): A Massive Helium-shell Double Detonation on a Sub-Chandrasekhar-mass White Dwarf

Author

De, K, Kasliwal, MM, Polin, A, Nugent, PE, Bildsten, L, Adams, SM, Bellm, EC, Blagorodnova, N, Burdge, KB, Cannella, C, Cenko, SB, Dekany, RG, Feeney, M, Hale, D, Fremling, UC, Graham, MJ, Ho, AYQ, Jencson, JE, Kulkarni, SR, Laher, RR, Masci, FJ, Miller, AA, Patterson, MT, Rebbapragada, U, Riddle, RL, Shupe, DL, and Smith, RM

Subjects
supernovae: general, supernovae: individual, surveys, white dwarfs, astro-ph.HE, astro-ph.SR, Astronomy & Astrophysics, Astronomical and Space Sciences
Abstract

The detonation of a helium shell on a white dwarf (WD) has been proposed as a possible explosion triggering mechanism for SNe Ia. Here, we report ZTF 18aaqeasu (SN 2018byg/ATLAS 18pqq), a peculiar Type I supernova, consistent with being a helium-shell double-detonation. With a rise time of ≈18 days from explosion, the transient reached a peak absolute magnitude of M R ≈ -18.2 mag, exhibiting a light curve akin to sub-luminous SN 1991bg-like SNe Ia, albeit with an unusually steep increase in brightness within a week from explosion. Spectra taken near peak light exhibit prominent Si absorption features together with an unusually red color (g - r ≈ 2 mag) arising from nearly complete line blanketing of flux blueward of 5000 . This behavior is unlike any previously observed thermonuclear transient. Nebular phase spectra taken at and after ≈30 days from peak light reveal evidence of a thermonuclear detonation event dominated by Fe-group nucleosynthesis. We show that the peculiar properties of ZTF 18aaqeasu are consistent with the detonation of a massive (≈0.15 ) helium shell on a sub-Chandrasekhar mass (≈0.75 ) WD after including mixing of ≈0.2 of material in the outer ejecta. These observations provide evidence of a likely rare class of thermonuclear supernovae arising from detonations of massive helium shells.

Published
2019

9. The zwicky transient facility: System overview, performance, and first results

Author

Bellm, EC, Kulkarni, SR, Graham, MJ, Dekany, R, Smith, RM, Riddle, R, Masci, FJ, Helou, G, Prince, TA, Adams, SM, Barbarino, C, Barlow, T, Bauer, J, Beck, R, Belicki, J, Biswas, R, Blagorodnova, N, Bodewits, D, Bolin, B, Brinnel, V, Brooke, T, Bue, B, Bulla, M, Burruss, R, Cenko, SB, Chang, CK, Connolly, A, Coughlin, M, Cromer, J, Cunningham, V, De, K, Delacroix, A, Desai, V, Duev, DA, Eadie, G, Farnham, TL, Feeney, M, Feindt, U, Flynn, D, Franckowiak, A, Frederick, S, Fremling, C, Gal-Yam, A, Gezari, S, Giomi, M, Goldstein, DA, Golkhou, VZ, Goobar, A, Groom, S, Hacopians, E, Hale, D, Henning, J, Ho, AYQ, Hover, D, Howell, J, Hung, T, Huppenkothen, D, Imel, D, Ip, WH, Ivezić, Ž, Jackson, E, Jones, L, Juric, M, Kasliwal, MM, Kaspi, S, Kaye, S, Kelley, MSP, Kowalski, M, Kramer, E, Kupfer, T, Landry, W, Laher, RR, Lee, CD, Lin, HW, Lin, ZY, Lunnan, R, Mahabal, A, Mao, P, Miller, AA, Monkewitz, S, Murphy, P, Ngeow, CC, Nordin, J, Nugent, P, Ofek, E, Patterson, MT, Penprase, B, Porter, M, Rauch, L, Rebbapragada, U, Reiley, D, Rigault, M, Rodriguez, H, van Roestel, J, Rusholme, B, van Santen, J, Schulze, S, Shupe, DL, and Singer, LP

Subjects
instrumentation: photometers, telescopes, astro-ph.IM, Astronomical And Space Sciences, Astronomy & Astrophysics, Astronomical and Space Sciences
Abstract

The Zwicky Transient Facility (ZTF) is a new optical time-domain survey that uses the Palomar 48 inch Schmidt telescope. A custom-built wide-field camera provides a 47 deg 2 field of view and 8 s readout time, yielding more than an order of magnitude improvement in survey speed relative to its predecessor survey, the Palomar Transient Factory. We describe the design and implementation of the camera and observing system. The ZTF data system at the Infrared Processing and Analysis Center provides near-real-time reduction to identify moving and varying objects. We outline the analysis pipelines, data products, and associated archive. Finally, we present on-sky performance analysis and first scientific results from commissioning and the early survey. ZTF’s public alert stream will serve as a useful precursor for that of the Large Synoptic Survey Telescope.

Published
2019

10. Reconnaissance of the HR 8799 Exosolar System II: Astrometry and Orbital Motion

Author

Pueyo, L., Soummer, R., Hoffmann, J., Oppenheimer, R., Graham, J. R., Zimmerman, N., Zhai, C., Wallace, J. K., Vescelus, F., Veicht, A., Vasisht, G., Truong, T., Sivaramakrishnan, A., Shao, M., Roberts Jr., L. C., Roberts, J. E., Rice, E., Parry, I. R., Nilsson, R., Luszcz-Cook, S., Lockhart, T., Ligon, E. R., King, D., Hinkley, S., Hillenbrand, L., Hale, D., Dekany, R., Crepp, J. R., Cady, E., Burruss, R., Brenner, D., Beichman, C., and Baranec, C.

Subjects
Astrophysics - Solar and Stellar Astrophysics
Abstract

We present an analysis of the orbital motion of the four sub-stellar objects orbiting HR8799. Our study relies on the published astrometric history of this system augmented with an epoch obtained with the Project 1640 coronagraph + Integral Field Spectrograph (IFS) installed at the Palomar Hale telescope. We first focus on the intricacies associated with astrometric estimation using the combination of an Extreme Adaptive Optics system (PALM-3000), a coronagraph and an IFS. We introduce two new algorithms. The first one retrieves the stellar focal plane position when the star is occulted by a coronagraphic stop. The second one yields precise astrometric and spectro-photometric estimates of faint point sources even when they are initially buried in the speckle noise. The second part of our paper is devoted to studying orbital motion in this system. In order to complement the orbital architectures discussed in the literature, we determine an ensemble of likely Keplerian orbits for HR8799bcde, using a Bayesian analysis with maximally vague priors regarding the overall configuration of the system. While the astrometric history is currently too scarce to formally rule out coplanarity, HR8799d appears to be misaligned with respect to the most likely planes of HR8799bce orbits. This misalignment is sufficient to question the strictly coplanar assumption made by various authors when identifying a Laplace resonance as a potential architecture. Finally, we establish a high likelihood that HR8799de have dynamical masses below 13 M_Jup using a loose dynamical survival argument based on geometric close encounters. We illustrate how future dynamical analyses will further constrain dynamical masses in the entire system., Comment: 26 pages, 18 figures

Published
2014
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11. PALM-3000: Exoplanet Adaptive Optics for the 5-meter Hale Telescope

Author

Dekany, R., Roberts, J., Burruss, R., Bouchez, A., Truong, T., Baranec, C., Guiwits, S., Hale, D., Angione, J., Trinh, T., Zolkower, J., Shelton, J. C., Palmer, D., Henning, J., Croner, E., Troy, M., McKenna, D., Tesch, J., Hildebrandt, S., and Milburn, J.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

We describe and report first results from PALM-3000, the second-generation astronomical adaptive optics facility for the 5.1-m Hale telescope at Palomar Observatory. PALM-3000 has been engineered for high-contrast imaging and emission spectroscopy of brown dwarfs and large planetary mass bodies at near-infrared wavelengths around bright stars, but also supports general natural guide star use to V ~ 17. Using its unique 66 x 66 actuator deformable mirror, PALM-3000 has thus far demonstrated residual wavefront errors of 141 nm RMS under 1 arcsecond seeing conditions. PALM-3000 can provide phase conjugation correction over a 6.4 x 6.4 arcsecond working region at an observing wavelength of 2.2 microns, or full electric field (amplitude and phase) correction over approximately one half of this field. With optimized back-end instrumentation, PALM-3000 is designed to enable as high as 10e-7 contrast at ~1 arc second angular separation, after including post-observation speckle suppression processing. While optimization of the adaptive optics system is ongoing, we have already successfully commissioned five back-end science instruments and begun a major exoplanet characterization survey, Project 1640, with our partners at American Museum of Natural History and Jet Propulsion Laboratory., Comment: 13 pages, 6 figures, 5 tables; Accepted for publication in the Astrophysical Journal

Published
2013
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12. Reconnaissance of the HR 8799 Exosolar System I: Near IR Spectroscopy

Author

Oppenheimer, B. R., Baranec, C., Beichman, C., Brenner, D., Burruss, R., Cady, E., Crepp, J. R., Dekany, R., Fergus, R., Hale, D., Hillenbrand, L., Hinkley, S., Hogg, David W., King, D., Ligon, E. R., Lockhart, T., Nilsson, R., Parry, I. R., Pueyo, L., Rice, E., Roberts, J. E., Roberts, Jr., L. C., Shao, M., Sivaramakrishnan, A., Soummer, R., Truong, T., Vasisht, G., Veicht, A., Vescelus, F., Wallace, J. K., Zhai, C., and Zimmerman, N.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

We obtained spectra, in the wavelength range \lambda = 995 - 1769 nm, of all four known planets orbiting the star HR 8799. Using the suite of instrumentation known as Project 1640 on the Palomar 5-m Hale Telescope, we acquired data at two epochs. This allowed for multiple imaging detections of the companions and multiple extractions of low-resolution (R ~ 35) spectra. Data reduction employed two different methods of speckle suppression and spectrum extraction, both yielding results that agree. The spectra do not directly correspond to those of any known objects, although similarities with L and T-dwarfs are present, as well as some characteristics similar to planets such as Saturn. We tentatively identify the presence of CH_4 along with NH_3 and/or C_2H_2, and possibly CO_2 or HCN in varying amounts in each component of the system. Other studies suggested red colors for these faint companions, and our data confirm those observations. Cloudy models, based on previous photometric observations, may provide the best explanation for the new data presented here. Notable in our data is that these presumably co-eval objects of similar luminosity have significantly different spectra; the diversity of planets may be greater than previously thought. The techniques and methods employed in this paper represent a new capability to observe and rapidly characterize exoplanetary systems in a routine manner over a broad range of planet masses and separations. These are the first simultaneous spectroscopic observations of multiple planets in a planetary system other than our own., Comment: Accepted for publication in The Astrophysical Journal 8 March 2013. Submitted 12 November 2012. Revised 11 February 2013 and 7 March 2013. 19 Pages, 10 Figures. Figure 4 is the money plot

Published
2013
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13. Supernova PTF 09uj: A possible shock breakout from a dense circumstellar wind

Author

Ofek, E. O., Rabinak, I., Neill, J. D., Arcavi, I., Cenko, S. B., Waxman, E., Kulkarni, S. R., Yam, A. Gal, Nugent, P. E., Bildsten, L., Bloom, J. S., Filippenko, A. V., Forster, K., Howell, D. A., Jacobsen, J., Kasliwal, M. M., Law, N., Martin, C., Poznanski, D., Quimby, R. M., Shen, K. J., Sullivan, M., Dekany, R., Rahmer, G., Hale, D., Smith, R., Zolkower, J., Velur, V., Walters, R., Henning, J., Bui, K., and McKenna, D.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Type-IIn supernovae (SNe), which are characterized by strong interaction of their ejecta with the surrounding circumstellar matter (CSM), provide a unique opportunity to study the mass-loss history of massive stars shortly before their explosive death. We present the discovery and follow-up observations of a Type IIn SN, PTF 09uj, detected by the Palomar Transient Factory (PTF). Serendipitous observations by GALEX at ultraviolet (UV) wavelengths detected the rise of the SN light curve prior to the PTF discovery. The UV light curve of the SN rose fast, with a time scale of a few days, to a UV absolute AB magnitude of about -19.5. Modeling our observations, we suggest that the fast rise of the UV light curve is due to the breakout of the SN shock through the dense CSM (n~10^10 cm^-3). Furthermore, we find that prior to the explosion the progenitor went through a phase of high mass-loss rate (~0.1 solar mass per year) that lasted for a few years. The decay rate of this SN was fast relative to that of other SNe IIn., Comment: Accepted to Apj, 6 pages, 4 figures

Published
2010
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14. Hydrogen-poor superluminous stellar explosions

Author

Quimby, R. M., Kulkarni, S. R., Kasliwal, M. M., Gal-Yam, A., Arcavi, I., Sullivan, M., Nugent, P., Thomas, R., Howell, D. A., Nakar, E., Bildsten, L., Theissen, C., Law, N., Dekany, R., Rahmer, G., Hale, D., Smith, R., Ofek, E. O., Zolkower, J., Velur, V., Walters, R., Henning, J., Bui, K., McKenna, D., Poznanski, D., Cenko, S. B., and Levitan, D.

Subjects
Astrophysics - Cosmology and Extragalactic Astrophysics
Abstract

Supernovae (SNe) are stellar explosions driven by gravitational or thermonuclear energy, observed as electromagnetic radiation emitted over weeks or more. In all known SNe, this radiation comes from internal energy deposited in the outflowing ejecta by either radioactive decay of freshly-synthesized elements (typically 56Ni), stored heat deposited by the explosion shock in the envelope of a supergiant star, or interaction between the SN debris and slowly-moving, hydrogen-rich circumstellar material. Here we report on a new class of luminous SNe whose observed properties cannot be explained by any of these known processes. These include four new SNe we have discovered, and two previously unexplained events (SN 2005ap; SCP 06F6) that we can now identify as members. These SNe are all ~10 times brighter than SNe Ia, do not show any trace of hydrogen, emit significant ultra-violet (UV) flux for extended periods of time, and have late-time decay rates which are inconsistent with radioactivity. Our data require that the observed radiation is emitted by hydrogen-free material distributed over a large radius (~10^15 cm) and expanding at high velocities (>10^4 km s^-1). These long-lived, UV-luminous events can be observed out to redshifts z>4 and offer an excellent opportunity to study star formation in, and the interstellar medium of, primitive distant galaxies., Comment: Accepted to Nature. Press embargoed until 2011 June 8, 18:00 UT

Published
2009
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15. The Palomar Transient Factory: System Overview, Performance and First Results

Author

Law, N. M., Kulkarni, S. R., Dekany, R. G., Ofek, E. O., Quimby, R. M., Nugent, P. E., Surace, J., Grillmair, C. C., Bloom, J. S., Kasliwal, M. M., Bildsten, L., Brown, T., Cenko, S. B., Ciardi, D., Croner, E., Djorgovski, S. G., van Eyken, J. C., Filippenko, A. V., Fox, D. B., Gal-Yam, A., Hale, D., Hamam, N., Helou, G., Henning, J. R., Howell, D. A., Jacobsen, J., Laher, R., Mattingly, S., McKenna, D., Pickles, A., Poznanski, D., Rahmer, G., Rau, A., Rosing, W., Shara, M., Smith, R., Starr, D., Sullivan, M., Velur, V., Walters, R. S., and Zolkower, J.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

The Palomar Transient Factory (PTF) is a fully-automated, wide-field survey aimed at a systematic exploration of the optical transient sky. The transient survey is performed using a new 8.1 square degree camera installed on the 48-inch Samuel Oschin telescope at Palomar Observatory; colors and light curves for detected transients are obtained with the automated Palomar 60-inch telescope. PTF uses eighty percent of the 1.2-m and fifty percent of the 1.5-m telescope time. With an exposure of 60-s the survey reaches a depth of approximately 21.3 in g' and 20.6 in R (5 sigma, median seeing). Four major experiments are planned for the five-year project: 1) a 5-day cadence supernova search; 2) a rapid transient search with cadences between 90 seconds and 1 day; 3) a search for eclipsing binaries and transiting planets in Orion; and 4) a 3-pi sr deep H-alpha survey. PTF provides automatic, realtime transient classification and follow up, as well as a database including every source detected in each frame. This paper summarizes the PTF project, including several months of on-sky performance tests of the new survey camera, the observing plans and the data reduction strategy. We conclude by detailing the first 51 PTF optical transient detections, found in commissioning data., Comment: 12 pages, 11 figures, 3 tables, submitted to PASP

Published
2009
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16. Lipid Profiles, Inflammatory Markers, and Insulin Therapy in Youth with Type 2 Diabetes

Author

McKay, S., Haymond, M., Anderson, B., Bush, C., Gunn, S., Holden, H., Jones, S.M., Jeha, G., McGirk, S., Thamotharan, S., Cuttler, L., Abrams, E., Casey, T., Dahms, W., Ievers-Landis, C., Kaminski, B., Koontz, M., MacLeish, S., McGuigan, P., Narasimhan, S., Geffner, M., Barraza, V., Chang, N., Conrad, B., Dreimane, D., Estrada, S., Fisher, L., Fleury-Milfort, E., Hernandez, S., Hollen, B., Kaufman, F., Law, E., Mansilla, V., Miller, D., Muñoz, C., Ortiz, R., Ward, A., Wexler, K., Xu, Y.K., Yasuda, P., Berkowitz, R., Boyd, S., Johnson, B., Kaplan, J., Keating, C., Lassiter, C., Lipman, T., McGinley, G., McKnight, H., Schwartzman, B., Willi, S., Arslanian, S., Foster, S., Galvin, B., Hannon, T., Kriska, A., Marcus, M., Songer, T., Venditti, E., Goland, R., Gallagher, D., Kringas, P., Leibel, N., Ng, D., Ovalles, M., Seidman, D., Laffel, L., Goebel-Fabbri, A., Hall, M., Higgins, L., Keady, J., Malloy, M., Milaszewski, K., Rasbach, L., Nathan, D.M., Angelescu, A., Bissett, L., Ciccarelli, C., Delahanty, L., Goldman, V., Hardy, O., Larkin, M., Levitsky, L., McEachern, R., Norman, D., Nwosu, D., Park-Bennett, S., Richards, D., Sherry, N., Steiner, B., Tollefsen, S., Carnes, S., Dempsher, D., Flomo, D., Whelan, T., Wolff, B., Bowerman, D., Bristol, S., Bulger, J., Hartsig, J., Izquierdo, R., Kearns, J., Saletsky, R., Trief, P., Zeitler, P., Abramson, N., Bradhurst, A., Celona-Jacobs, N., Higgins, J., Kelsey, M., Klingensmith, G., Witten, T., Copeland, K., Boss, E., Brown, R., Chadwick, J., Chalmers, L., Chernausek, S., Hebensperger, A., Macha, C., Newgent, R., Nordyke, A., Olson, D., Poulsen, T., Pratt, L., Preske, J., Schanuel, J., Sternlof, S., Lynch, J., Amodei, N., Barajas, R., Cody, C., Hale, D., Hernandez, J., Ibarra, C., Morales, E., Rivera, S., Rupert, G., Wauters, A., White, N., Arbeláez, A., Jones, J., Jones, T., Sadler, M., Tanner, M., Timpson, A., Welch, R., Caprio, S., Grey, M., Guandalini, C., Lavietes, S., Rose, P., Syme, A., Tamborlane, W., Hirst, K., Edelstein, S., Feit, P., Grover, N., Long, C., Pyle, L., Linder, B., Harting, J., Shepherd, J., Fan, B., Marquez, L., Sherman, M., Wang, J., Nichols, M., Mayer-Davis, E., Liu, Y., Lima, J., Puccella, J., Ricketts, E., Danis, R., Domalpally, A., Goulding, A., Neill, S., Vargo, P., Wilfley, D., Aldrich-Rasche, D., Franklin, K., Massmann, C., O'Brien, D., Patterson, J., Tibbs, T., Van Buren, D., Palmert, M., Ratner, R., Dremaine, D., Silverstein, J., Levitt Katz, Lorraine E., Bacha, Fida, Gidding, Samuel S., Weinstock, Ruth S., El ghormli, Laure, Libman, Ingrid, Nadeau, Kristen J., Porter, Kristin, and Marcovina, Santica

Published
2018
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17. Cardiac Biomarkers in Youth with Type 2 Diabetes Mellitus: Results from the TODAY Study

Author

McKay, S., Haymond, M., Anderson, B., Bush, C., Gunn, S., Holden, H., Jones, S.M., Jeha, G., McGirk, S., Thamotharan, S., Cuttler, L., Abrams, E., Casey, T., Dahms, W., Ievers-Landis, C., Kaminski, B., Koontz, M., MacLeish, S., McGuigan, P., Narasimhan, S., Geffner, M., Barraza, V., Chang, N., Conrad, B., Dreimane, D., Estrada, S., Fisher, L., Fleury-Milfort, E., Hernandez, S., Hollen, B., Kaufman, F., Law, E., Mansilla, V., Miller, D., Muñoz, C., Ortiz, R., Ward, A., Wexler, K., Xu, Y.K., Yasuda, P., Levitt Katz, L., Berkowitz, R., Boyd, S., Johnson, B., Kaplan, J., Keating, C., Lassiter, C., Lipman, T., McGinley, G., McKnight, H., Schwartzman, B., Willi, S., Arslanian, S., Bacha, F., Foster, S., Galvin, B., Hannon, T., Kriska, A., Libman, I., Marcus, M., Porter, K., Songer, T., Venditti, E., Goland, R., Gallagher, D., Kringas, P., Leibel, N., Ng, D., Ovalles, M., Seidman, D., Laffel, L., Goebel-Fabbri, A., Hall, M., Higgins, L., Keady, J., Malloy, M., Milaszewski, K., Rasbach, L., Nathan, D.M., Angelescu, A., Bissett, L., Ciccarelli, C., Delahanty, L., Goldman, V., Hardy, O., Larkin, M., Levitsky, L., McEachern, R., Norman, D., Nwosu, D., Park-Bennett, S., Richards, D., Sherry, N., Steiner, B., Tollefsen, S., Carnes, S., Dempsher, D., Flomo, D., Whelan, T., Wolff, B., Weinstock, R., Bowerman, D., Bristol, S., Bulger, J., Hartsig, J., Izquierdo, R., Kearns, J., Saletsky, R., Trief, P., Zeitler, P., Abramson, N., Bradhurst, A., Celona-Jacobs, N., Higgins, J., Kelsey, M., Klingensmith, G., Nadeau, K., Witten, T., Copeland, K., Boss, E., Brown, R., Chadwick, J., Chalmers, L., Chernausek, S., Hebensperger, A., Macha, C., Newgent, R., Nordyke, A., Olson, D., Poulsen, T., Pratt, L., Preske, J., Schanuel, J., Sternlof, S., Lynch, J., Amodei, N., Barajas, R., Cody, C., Hale, D., Hernandez, J., Ibarra, C., Morales, E., Rivera, S., Rupert, G., Wauters, A., White, N., Arbeláez, A., Jones, J., Jones, T., Sadler, M., Tanner, M., Timpson, A., Welch, R., Caprio, S., Grey, M., Guandalini, C., Lavietes, S., Rose, P., Syme, A., Tamborlane, W., Hirst, K., Edelstein, S., Feit, P., Grover, N., Long, C., Pyle, L., Linder, B., Marcovina, S.M., Harting, J., Shepherd, J., Fan, B., Marquez, L., Sherman, M., Wang, J., Nichols, M., Mayer-Davis, E., Liu, Y., Lima, J., Gidding, S., Puccella, J., Ricketts, E., Danis, R., Domalpally, A., Goulding, A., Neill, S., Vargo, P., Wilfley, D., Aldrich-Rasche, D., Franklin, K., Massmann, C., O'Brien, D., Patterson, J., Tibbs, T., Van Buren, D., Palmert, M., Ratner, R., Dremaine, D., Silverstein, J., Gidding, Samuel S., Bacha, Fida, Bjornstad, Petter, Levitt Katz, Lorraine E., Levitsky, Lynne L., Lynch, Jane, Tryggestad, Jeanie B., Weinstock, Ruth S., El ghormli, Laure, and Lima, Joao A.C.

Published
2018
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18. Imaging the disk around the luminous young star LkHalpha 101 with infrared interferometry

Author

Tuthill, P. G., Monnier, J. D., Danchi, W. C., Hale, D. D. S., and Townes, C. H.

Subjects
Astrophysics
Abstract

The Herbig Ae/Be star LkHalpha 101 has been imaged at high angular resolution at a number of wavelengths in the near-infrared (from 1 to 3 microns) using the Keck 1 Telescope, and also observed in the mid-infrared (11.15 microns) using the U.C. Berkeley Infrared Spatial Interferometer (ISI). The resolved circular disk with a central hole or cavity reported in Tuthill et al. (2001) is confirmed. This is consistent with an almost face-on view (inclination < 35 deg) onto a luminous pre- or early-main sequence object surrounded by a massive circumstellar disk. With a multiple-epoch study spanning almost four years, relative motion of the binary companion has been detected, together with evidence for changes in the brightness distribution of the central disk/star. The resolution of the LkHalpha 101 disk by ISI mid-infrared interferometry constitutes the first such measurement of a young stellar object in this wavelength region. The angular size was found to increase only slowly from 1.6 to 11.15 microns, inconsistent with standard power-law temperature profiles usually encountered in the literature, supporting instead models with a hot inner cavity and relatively rapid transition to a cool or tenuous outer disk. The radius of the dust-free inner cavity is consistent with a model of sublimation of dust in equilibrium with the stellar radiation field. Measurements from interferometry have been combined with published photometry enabling an investigation of the energetics and fundamental properties of this prototypical system., Comment: Appearing in Astrophysical Journal. 24 pages; 8 figures

Published
2002
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19. Mid-infrared interferometry on spectral lines: III. Ammonia and Silane around IRC+10216 and VY CMa

Author

Monnier, J. D., Danchi, W. C., Hale, D. S., Tuthill, P. G., and Townes, C. H.

Subjects
Astrophysics
Abstract

Using the U.C. Berkeley Infrared Spatial Interferometer with an RF filterbank, the first interferometric observations of mid-infrared molecular absorption features of ammonia (NH_3) and silane (SiH_4) with very high spectral resolution (R ~ 100000) were made. Under the assumptions of spherical symmetry and uniform outflow, these new data permitted the molecular stratification around carbon star IRC+10216 and red supergiant VY CMa to be investigated. For IRC+10216, both ammonia and silane were found to form in the dusty outflow significantly beyond both the dust formation and gas acceleration zones. Specifically, ammonia was found to form before silane in a region of decaying gas turbulence (>~ 20 R_star), while the silane is produced in a region of relatively smooth gas flow much further from the star (>~ 80 R_star). The depletion of gas-phase SiS onto grains soon after dust formation may fuel silane-producing reactions on the grain surfaces. For VY CMa, a combination of interferometric and spectral observations suggest that NH_3 is forming near the termination of the gas acceleration phase in a region of high gas turbulence (~ 40 R_star)., Comment: 31 Pages, Accepted in the Astrophysical Journal

Published
2000
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20. Mid-infrared interferometry on spectral lines: II. Continuum (dust) emission around IRC+10216 and VY CMa

Author

Monnier, J. D., Danchi, W. C., Hale, D. S., Lipman, E. A., Tuthill, P. G., and Townes, C. H.

Subjects
Astrophysics
Abstract

The U. C. Berkeley Infrared Spatial Interferometer has measured the mid-infrared visibilities of the carbon star IRC+10216 and the red supergiant VY CMa. The dust shells around these sources have been previously shown to be time-variable, and these new data are used to probe the evolution of the dust shells on a decade time-scale, complementing contemporaneous studies at other wavelengths. Self-consistent, spherically-symmetric models at maximum and minimum light both show the inner radius of the IRC+10216 dust shell to be much larger (150 mas) than that expected from the dust condensation temperature, implying that dust production has slowed or stopped in recent years. Apparently, dust does not form every pulsational cycle (638 days), and these mid-infrared results are consistent with recent near-IR imaging which indicates little or no new dust production in the last three years (Tuthill et al 2000). Spherically symmetric models failed to fit recent VY CMa data, implying that emission from the inner dust shell is highly asymmetric and/or time-variable., Comment: 18 pages, Accepted in the Astrophysical Journal

Published
2000
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21. Near and mid-IR sub-arcsecond structure of the dusty symbiotic star R Aqr

Author

Tuthill, P. G., Danchi, W. C., Hale, D. S., Monnier, J. D., and Townes, C. H.

Subjects
Astrophysics
Abstract

The results of a high-resolution interferometric campaign targeting the symbiotic long-period variable (LPV) R~Aqr are reported. With both near-infrared measurements on baselines out to 10m and mid-infrared data extending to 32m, we have been able to measure the characteristic sizes of regions from the photosphere of the LPV and its extended molecular atmosphere, out to the cooler circumstellar dust shell. The near-infrared data were taken using aperture masking interferometry on the Keck-I telescope and show R~Aqr to be partially resolved for wavelengths out to 2.2 microns but with a marked enlargement, possibly due to molecular opacity, at 3.1 microns. Mid-infrared interferometric measurements were obtained with the U.C. Berkeley Infrared Spatial Interferometer (ISI) operating at 11.15 microns from 1992 to 1999. Although this dataset is somewhat heterogeneous with incomplete coverage of the Fourier plane and sampling of the pulsation cycle, clear changes in the mid-infrared brightness distribution were observed, both as a function of position angle on the sky and as a function of pulsation phase. Spherically symmetric radiative transfer calculations of uniform-outflow dust shell models produce brightness distributions and spectra which partially explain the data, however limitations to this approximation are noted. Evidence for significant deviation from circular symmetry was found in the mid-infrared and more tentatively at 3.08 microns in the near-infrared, however no clear detection of binarity or of non-LPV elements in the symbiotic system is reported., Comment: Accepted to Astrophysical Journal. To appear in volume 534. 14 pages; 3 postscript figures

Published
2000
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22. BABAR silicon vertex tracker: Status and prospects

Author

Re, V, Bondioli, M, Bruinsma, M, Curry, S, Kirkby, D, Berryhill, J, Burke, S, Callahan, D, Campagnari, C, Cunha, A, Dahmes, B, Hale, D, Kyre, S, Richman, J, Stoner, J, Verkerke, W, Beck, T, Eisner, A M, Kroseberg, J, Lockman, W S, Nesom, G, Seiden, A, Spradlin, P, Wilson, M, Winstrom, L, Bozzi, C, Cibinetto, G, Piemontese, L, Brown, D, Charles, E, Dardin, S, Goozen, F, Gritsan, A, Kerth, L T, Lynch, G, Roe, N A, Chen, C, Lae, C K, Roberts, D, Simi, G, Lazzaro, A, Palombo, F, Snoek, H L, Ratti, L, Angelini, C, Batignani, G, Bettarini, S, Bosi, F, Bucci, F, Calderini, G, Carpinelli, M, Ceccanti, M, Forti, F, Cenci, R, Giorgi, M A, Lusiani, A, Mammini, P, Manfredi, P F, Marchiori, G, Mazur, M, Morganti, M, Morsani, F, Neri, N, Paoloni, E, Profeti, A, Rama, M, Rizzo, G, Walsh, J, Elmer, P, Long, O, Perazzo, A, Burchat, P, Edwards, A J, Majewski, S, Petersen, B A, Bona, M, Bianchi, F, Gamba, D, Trapani, P, Bomben, M, Bosisio, L, Cartaro, C, Cossutti, F, Della Ricca, G, Dittongo, S, Lanceri, L, Vitale, L, Datta, M, Mihalyi, A, and Cunha, *A

Subjects
silicon detector, radiation damage, charge accumulation
Abstract

The BABAR Silicon Vertex Tracker (SVT) has been efficiently operated for six years since the start of data taking in 1999. Due to higher than expected background levels some unforeseen effects have appeared. We discuss: a shift in the pedestal for the channels of the AToM readout chips that are most exposed to radiation; an anomalous increase in the bias leakage current for the modules in the outer layers. Estimates of future radiation doses and occupancies are shown together with the extrapolated detector performance and lifetime, in light of the new observations. (c) 2006 Elsevier B.V. All rights reserved.

Published
2006

26. Urogenital Dysfunction

Author

Kelvin, F. M., Hale, D. S., Strohbehn, K., Baert, A. L., editor, Sartor, K., editor, Bartram, Clive I., editor, and DeLancey, John O. L., editor

Published
2003
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27. Recent Results from the Cryogenic Dark Matter Search for Weakly Interacting Massive Particles

Author

Gaitskell, R. J., Abusaidi, R., Akerib, D. S., Barnes, P. D., Jr., Bauer, D. A., Bolozdynya, A., Brink, P. L., Bunker, R., Cabrera, B., Caldwell, D. O., Castle, J. P., Clarke, R. M., Colling, P., Crisler, M. B., Cummings, A., Da Silva, A., Davies, A. K., Dixon, R., Dougherty, B. L., Driscoll, D., Eichblatt, S., Emes, J., Golwala, S. R., Hale, D., Haller, E. E., Hellmig, J., Huber, M. E., Irwin, K. D., Jochum, J., Lipschultz, F. P., Lu, A., Mandic, V., Martinis, J. M., Nam, S. W., Nelson, H., Neuhauser, B., Penn, M. J., Perera, T. A., Isaac, M. C. Perillo, Pritychenko, B., Ross, R. R., Saab, T., Sadoulet, B., Schnee, R. W., Seitz, D. N., Shestople, P., Shutt, T., Smith, A., Smith, G. W., Sonnenschein, A. H., Spadafora, A. L., Stockwell, W., Taylor, J. D., White, S., Yellin, S., Young, B. A., and Cline, David B., editor

Published
2001
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28. Results of the Cryogenic Dark Matter Search

Author

Schnee, R. W., Abusaidi, R., Akerib, D. S., Barnes, P. D., Jr., Bauer, D. A., Bolozdynya, A., Brink, P. L., Bunker, R., Cabrera, B., Caldwell, D. O., Castle, J. P., Clarke, R. M., Colling, P., Crisler, M. B., Cummings, A., Da Silva, A., Davies, A. K., Dixon, R., Dougherty, B. L., Driscoll, D., Eichblatt, S., Emes, J., Gaitskell, R. J., Golwala, S. R., Hale, D., Haller, E. E., Hellmig, J., Huber, M. E., Irwin, K. D., Jochum, J., Lipschultz, F. P., Lu, A., Mandic, V., Martinis, J. M., Nam, S. W., Nelson, H., Neuhauser, B., Penn, M. J., Perera, T. A., Isaac, M. C. Perillo, Pritychenko, B., Ross, R. R., Saab, T., Sadoulet, B., Seitz, D. N., Shestople, P., Shutt, T., Smith, A., Smith, G. W., Sonnenschein, A. H., Spadafora, A. L., Stockwell, W., Taylor, J. D., White, S., Yellin, S., Young, B. A., and Klapdor-Kleingrothaus, H. V., editor

Published
2001
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29. Cardiac Biomarkers in Youth with Type 2 Diabetes Mellitus: Results from the TODAY Study

Author

Gidding, Samuel S., Bacha, Fida, Bjornstad, Petter, Katz, Lorraine E. Levitt, Levitsky, Lynne L., Lynch, Jane, Tryggestad, Jeanie B., Weinstock, Ruth S., El ghormli, Laure, Lima, Joao A.C., McKay, S., Haymond, M., Anderson, B., Bush, C., Gunn, S., Holden, H., Jones, S. M., Jeha, G., McGirk, S., Thamotharan, S., Cuttler, L., Abrams, E., Casey, T., Dahms, W., Ievers-Landis, C., Kaminski, B., Koontz, M., MacLeish, S., McGuigan, P., Narasimhan, S., Geffner, M., Barraza, V., Chang, N., Conrad, B., Dreimane, D., Estrada, S., Fisher, L., Fleury-Milfort, E., Hernandez, S., Hollen, B., Kaufman, F., Law, E., Mansilla, V., Miller, D., Muñoz, C., Ortiz, R., Ward, A., Wexler, K., Xu, Y. K., Yasuda, P., Katz, Levitt L., Berkowitz, R., Boyd, S., Johnson, B., Kaplan, J., Keating, C., Lassiter, C., Lipman, T., McGinley, G., McKnight, H., Schwartzman, B., Willi, S., Arslanian, S., Bacha, F., Foster, S., Galvin, B., Hannon, T., Kriska, A., Libman, I., Marcus, M., Porter, K., Songer, T., Venditti, E., Goland, R., Gallagher, D., Kringas, P., Leibel, N., Ng, D., Ovalles, M., Seidman, D., Laffel, L., Goebel-Fabbri, A., Hall, M., Higgins, L., Keady, J., Malloy, M., Milaszewski, K., Rasbach, L., Nathan, D. M., Angelescu, A., Bissett, L., Ciccarelli, C., Delahanty, L., Goldman, V., Hardy, O., Larkin, M., Levitsky, L., McEachern, R., Norman, D., Nwosu, D., Park-Bennett, S., Richards, D., Sherry, N., Steiner, B., Tollefsen, S., Carnes, S., Dempsher, D., Flomo, D., Whelan, T., Wolff, B., Weinstock, R., Bowerman, D., Bristol, S., Bulger, J., Hartsig, J., Izquierdo, R., Kearns, J., Saletsky, R., Trief, P., Zeitler, P., Abramson, N., Bradhurst, A., Celona-Jacobs, N., Higgins, J., Kelsey, M., Klingensmith, G., Nadeau, K., Witten, T., Copeland, K., Boss, E., Brown, R., Chadwick, J., Chalmers, L., Chernausek, S., Hebensperger, A., Macha, C., Newgent, R., Nordyke, A., Olson, D., Poulsen, T., Pratt, L., Preske, J., Schanuel, J., Sternlof, S., Lynch, J., Amodei, N., Barajas, R., Cody, C., Hale, D., Hernandez, J., Ibarra, C., Morales, E., Rivera, S., Rupert, G., Wauters, A., White, N., Arbeláez, A., Jones, J., Jones, T., Sadler, M., Tanner, M., Timpson, A., Welch, R., Caprio, S., Grey, M., Guandalini, C., Lavietes, S., Rose, P., Syme, A., Tamborlane, W., Hirst, K., Edelstein, S., Feit, P., Grover, N., Long, C., Pyle, L., Linder, B., Marcovina, S. M., Harting, J., Shepherd, J., Fan, B., Marquez, L., Sherman, M., Wang, J., Nichols, M., Mayer-Davis, E., Liu, Y., Lima, J., Gidding, S., Puccella, J., Ricketts, E., Danis, R., Domalpally, A., Goulding, A., Neill, S., Vargo, P., Wilfley, D., Aldrich-Rasche, D., Franklin, K., Massmann, C., O’Brien, D., Patterson, J., Tibbs, T., Van Buren, D., Palmert, M., Ratner, R., Dremaine, D., and Silverstein, J.

Published
2018
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30. The Cryogenic Dark Matter Search (CDMS)

Author

Sonnenschein, A., Bauer, D., Caldwell, D. O., Hale, D., Yellin, S., Barnes, P. D., Jr, DaSilva, A., Gaitskell, R. J., Golwala, S. R., Ross, R. R., Sadoulet, B., Seitz, D., Shutt, T., Smith, G., Stockwell, W., Therrien, R., White, S., Brink, P., Cabrera, B., Chugg, B., Clarke, R. M., Dougherty, B. L., Davies, A., Irwin, K., Nam, S. W., Penn, M. J., Akerib, D. S., Perera, T. A., Schnee, R., Emes, J., Haller, E. E., Knowlton, W. B., Smith, A., Taylor, J. D., Young, B. A., Schramm, David N., editor, and Galeotti, P., editor

Published
1997
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36. PO-36 Treatment of cancer-associated venous thromboembolism: 12-month outcomes of the placebo versus rivaroxaban randomisation of the SELECT-D trial

Author

Marshall, A., primary, Young, A.M., additional, Levine, M., additional, Hill, C., additional, Hale, D., additional, Thirlwall, J., additional, Wilkie, V., additional, French, K., additional, Kakkar, A.K., additional, Lokare, A., additional, Maraveyas, A., additional, Chapman, O., additional, Arif, A., additional, Petrou, S., additional, Maredza, M., additional, Hobbs, F.D.R., additional, and Dunn, J.A., additional

Published
2021
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41. Lessons learned from BaBar silicon vertex tracker, limits, and future perspectives of the detector

Author

Re, V., Kirkby, D., Bruinsma, M., Curry, S., Berryhill, J., Burke, S., Callahan, D., Campagnari, C., Dahmes, B., Hale, D., Hart, P., Kyre, S., Levy, S., Long, O., Mazur, M., Richman, J., Stoner, J., Verkerke, W., Beck, T., Eisner, A.M., Kroseberg, J., Lockman, W.S., Nesom, G., Seiden, A., Spradlin, E., Walkowiak, W., Wilson, M., Bozzi, C., Cibinetto, G., Piemontese, L., Snoek, H.L., Brown, D., Charles, E., Dardin, S., Goozen, F., Kerth, L.T., Gritsan, A., Lynch, G., Roe, N.A., Chen, C., Lae, C.K., Hulsbergen, W., Lillard, V., Roberts, D., Lazzaro, A., Palombo, F., Ratti, L., Manfredi, P.F., Mandelli, E., Angelini, C., Batignani, G., Bettarini, S., Bondioli, M., Bosi, F., Bucci, F., Calderini, G., Carpinelli, M., Ceccanti, M., Forti, F., Giorgi, M.A., Lusiani, A., Mammini, P., Marchiori, G., Morganti, M., Morsani, F., Neri, N., Paoloni, E., Profeti, A., Rama, M., Rizzo, G., Simi, G., Walsh, J., Elmer, P., Perazzo, A., Burchat, P., Edwards, A., Majewski, S., Petersen, B.A., Roat, C., Bona, M., Bianchi, F., Gamba, D., Trapani, P., Bosisio, L., Cartaro, C., Cossuti, F., Ricca, G. Della, Dittongo, S., Grancagnolo, S., Lanceri, L., Vitale, L., Datta, M., and Mihalyi, A.

Subjects
Silicon diodes, Radiation warning systems, Detectors, Business, Electronics, Electronics and electrical industries
Abstract

The silicon vertex tracker (SVT) of the BaBar experiment at PEP-II is described. This is the crucial device for the measurement of the B meson decay vertices to extract charge-conjugation parity (CP) asymmetries. It consists of five layers of double sided ac-coupled silicon strip detectors, read out by a full-custom integrated circuit, capable of simultaneous acquisition, digitization, and transmission of data. It represents the core of the BaBar tracking system, providing position measurements with a precision of 10 [micro]m (inner layers) and 30 [micro]m (outer layers). The relevant performances of the SVT are presented, and the experience acquired during the construction, installation, and the first five years of data-taking is described. Innovative solutions are highlighted, like the sophisticated alignment procedure, imposed by the design of the silicon tracker, integrated in the beamline elements and mechanically separated from the other parts of BaBar. The harshness of the background conditions in the interaction region required several studies on the radiation damage of the sensors and the front-end chips, whose results are presented. Over the next five years the luminosity is predicted to increase by a factor three, leading to radiation and occupancy levels significantly exceeding the detector design. Extrapolation of future radiation doses and occupancies is shown together with the expected detector performance and lifetime. Upgrade scenarios to deal with the increased luminosity and backgrounds are discussed. Index Terms--Radiation damage, silicon detector.

Published
2005

42. Sensors for the CDF Run2b silicon detector

Author

Akimoto, T., Aoki, M., Azzi, P., Bacchetta, N., Behari, S., Benjamin, D., Bisello, D., Bolla, G., Booth, P., Bortoletto, D., Burghard, A., Busetto, G., Cabrera, S., Canepa, A., Cardoso, G., Chertok, M., Ciobanu, C.I., Cooke, P., Derylo, G., Fang, I., Feng, E.J., Fernandez, J.P., Flaugher, B., Freeman, J., Galtieri, L., Galyardt, J., Garcia-Sciveres, M., Giurgiu, G., Gorelov, I., Haber, C., Hale, D., Hara, K., Harr, R., Hill, C., Hoeferkamp, M., Hoff, J., Holbrook, B., Hong, S.C., Hrycyk, M., Hsiung, T.H., Incandela, J., Jeon, E.J., Joo, K.K., Junk, T., Kahkola, H., Karjalainen, S., Kim, S., Kobayashi, K., Kong, D.J., Krieger, B., Kruse, M., Kyre, S., Lander, R., Landry, T., Lauhakangas, R., Lee, J., Lu, R.-S., Lujan, P.J., Lukens, P., Mandelli, E., Manea, C., Maksimovic, P., Merkel, P., Min, S.N., Moccia, S., Nakamura, Y., Nakano, I., Naoumov, D., Nelson, T., Nord, B., Novak, J., Okusawa, T., Orava, R., Orlov, Y., Osterberg, K., Pantano, D., Pavlicek, V., Pellett, D., Pursley, J., Riipinen, P., Schuyler, B., Seidel, S., Shenai, A., Soha, A., Stuart, D., Tanaka, R., Tavi, M., Von der Lippe, H., Walder, J.-P., Wang, Z., Watje, P., Weber, M., Wester, W., Yamamoto, Kenichi, Yang, Y.C., Yao, W., Yarema, R., Yoshitama, H., Yun, J.C., Zetti, F., Zimmerman, T., Zimmermann, S., and Zucchelli, S.

Subjects
Hamamatsu Photonic Systems -- Product development, Silicon diodes -- Product development, Photographic industry -- Product development, Sensors -- Usage, Business, Electronics, Electronics and electrical industries
Abstract

We describe the characteristics of silicon microstrip sensors fabricated by Hamamatsu Photonics for the CDF Run 2b silicon detector. A total of 953 sensors, including 117 prototype sensors, have been produced and tested. Five sensors were irradiated with neutrons up to 1.4 x [10.sup.14] n/[cm.sup.2] as a part of the sensor quality assurance program. The electrical and mechanical characteristics are found to be superior in all aspects and fulfill our specifications. We comment on charge-up susceptibility of the sensors that employ a (100) crystal structure.

Published
2004

43. CDF Run IIb silicon detector: electrical performance and deadtime-less operation

Author

Akimoto, T., Aoki, M., Azzi, P., Bacchetta, N., Behari, S., Benjamin, D., Bisello, D., Bolla, G., Bortoletto, D., Busetto, G., Cabrera, S., Canepa, A., Cardoso, G., Chertok, M., Ciobanu, C.I., Derylo, G., Fang, I., Feng, E.J., Fernandez, J.P., Flaugher, B., Freeman, J., Galtieri, L., Galyardt, J., Garcia-Sciveres, M., Giurgiu, G., Haber, C., Hale, D., Hara, K., Harr, R., Hill, C., Hoff, J., Holbrook, B., Hong, S.C., Hrycyk, M., Hsiung, T.H., Incandela, J., Jeon, E.J., Joo, K.K., Junk, T., Kahkola, H., Karjalainen, S., Kim, S., Kobayashi, K., Kong, D.J., Krieger, B., Kruse, M., Kuznetsova, N., Kyre, S., Lander, R., Landry, T., Lauhakangas, R., Lee, J., Lu, R.-S., Lujan, P., Lukens, P., Mandelli, E., Manea, C., Maksimovic, P., Merkel, P., Min, S.N., Moccia, S., Nakano, I., Nelson, T., Nord, B., Novak, J., Okusawa, T., Orava, R., Orlov, Y., Osterberg, K., Pantano, D., Pavlicek, V., Pellett, D., Pursley, J., Riipinen, P., Schuyler, B., Shenai, A., Soha, A., Stuart, D., Tanaka, R., Tavi, M., Von der Lippe, H., Walder, J.-P., Wang, Z., Weber, Marc, Wester, W., Yamamoto, Kenichi, Yang, Y.C., Yao, W., Yarema, R., Yun, J.C., Zetti, F., Zimmerman, T., Zimmermann, S., and Zucchelli, S.

Subjects
Nuclear physics -- Research, Detectors, Business, Electronics, Electronics and electrical industries
Abstract

The main building block and readout unit of the planned CDF Run IIb silicon detector is a 'stave,' a highly integrated mechanical, thermal, and electrical structure. One of its characteristic features is a copper-on-Kapton flexible cable for power, high voltage, data transmission, and control signals that is placed directly below the silicon microstrip sensors. The dense packaging makes deadtime-less operation of the stave a challenge since coupling of bus cable activity into the silicon sensors must be suppressed efficiently. The stave design features relevant for deadtime-less operation are discussed. The electrical performance achieved with stave prototypes is presented. Index Terms--CDF, deadtime-less, Run IIb, silicon tracker, SVX4.

Published
2004

44. Status and prospects of the BaBar SVT

Author

Re, V., Bruinsma, M., Curry, S., Kirkby, D., Berryhill, J., Burke, S., Callahan, D., Campagnari, C., Dahmes, B., Hale, D., Hart, P., Kyre, S., Levy, S., Long, O., Mazur, M., Richman, J., Stoner, J., Verkerke, W., Beck, T., Eisner, A.M., Kroseberg, J., Lockman, W.S., Nesom, G., Seiden, A., Spradlin, P., Walkowiak, W., Wilson, M., Bozzi, C., Cibinetto, G., Piemontese, L., Snoek, H.L., Brown, D., Charles, E., Dardin, S., Goozen, F., Kerth, L.T., Gritsan, A., Lynch, G., Roe, N.A., Chen, C., Hulsbergen, W., Lae, C.K., Lillard, V., Roberts, D., Lazzaro, A., Palombo, F., Ratti, L., Manfredi, P.F., Mandelli, E., Angelini, C., Batignani, G., Bettarini, S., Bondioli, M., Bosi, F., Bucci, F., Calderini, G., Carpinelli, M., Ceccanti, M., Forti, F., Giorgi, M.A., Lusiani, A., Mammini, P., Marchiori, G., Morganti, M., Morsani, F., Neri, N., Paoloni, E., Profeti, A., Rama, M., Rizzo, G., Simi, G., Walsh, J., Elmer, P., Perazzo, A., Burchat, P., Edwards, A.J., Majewski, S., Petersen, B.A., Roat, C., Bona, M., Bianchi, F., Gamba, D., Trapani, P., Bosisio, L., Cartaro, C., Cossutti, F., Della Ricca, G., Dittongo, S., Grancagnolo, S., Lanceri, L., Vitale, L., Datta, M., and Mihalyi, A.

Published
2006
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45. The CDF Run IIb Silicon Detector: Design, preproduction, and performance

Author

Akimoto, T., Aoki, M., Azzi, P., Bacchetta, N., Behari, S., Benjamin, D., Bisello, D., Bolla, G., Bortoletto, D., Burghard, A., Busetto, G., Cabrera, S., Canepa, A., Cardoso, G., Chertok, M., Ciobanu, C.I., Derylo, G., Fang, I., Feng, E.J., Fernandez, J.P., Flaugher, B., Freeman, J., Galtieri, L., Galyardt, J., Garcia-Sciveres, M., Giurgiu, G., Gorelov, I., Haber, C., Hale, D., Hara, K., Harr, R., Hill, C., Hoeferkamp, M., Hoff, J., Holbrook, B., Hong, S.C., Hrycyk, M., Hsiung, T.H., Incandela, J., Jeon, E.J., Joo, K.K., Junk, T., Kahkola, H., Karjalainen, S., Kim, S., Kobayashi, K., Kong, D.J., Krieger, B., Kruse, M., Kuznetsova, N., Kyre, S., Lander, R., Landry, T., Lauhakangas, R., Lee, J., Lu, R.-S., Lujan, P., Lukens, P., Mandelli, E., Manea, C., Maksimovic, P., Merkel, P., Min, S.N., Moccia, S., Nakano, I., Naoumov, D., Nelson, T., Nord, B., Novak, J., Okusawa, T., Orava, R., Orlov, Y., Osterberg, K., Pantano, D., Pavlicek, V., Pellett, D., Pursley, J., Riipinen, P., Schuyler, B., Seidel, S., Shenai, A., Soha, A., Stuart, D., Tanaka, R., Tavi, M., Von der Lippe, H., Walder, J.-P., Wang, Z., Watje, P., Weber, Marc, Wester, W., Yamamoto, K., Yang, Y.C., Yao, W., Yarema, R., Yun, J.C., Zetti, F., Zimmerman, T., Zimmermann, S., and Zucchelli, S.

Published
2006
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46. The BaBar silicon-vertex tracker: performance, running experience, and radiation-damage studies

Author

Re, V., Borean, C., Bozzi, C., Carassiti, V., Ramusino, A. Cotta, Piemontese, L., Breon, A.B., Brown, D., Clark, A.R., Goozen, F., Hernikl, C., Kerth, L.T., Gritsan, A., Lynch, G., Perazzo, A., Roe, N.A., Zizka, G., Roberts, D., Schieck, J., Brenna, E., Citterio, M., Lanni, F., Palombo, F., Ratti, L., Manfredi, P.F., Angelini, C., Batignani, G., Bettarini, S., Bondioli, M., Bosi, F., Bucci, F., Calderini, G., Carpinelli, M., Ceccanti, M., Forti, F., Gagliardi, D., Giorgi, M.A., Lusiani, A., Mammini, P., Morganti, M., Morsani, F., Neri, N., Paoloni, E., Profeti, A., Rama, M., Rizzo, G., Sandrelli, F., Simi, G., Triggiani, G., Walsh, J., Burchat, P., Cheng, C., Kirkby, D., Meyer, T.I., Roat, C., Bona, M., Bianchi, F., Gamba, D., Trapani, P., Bosisio, L., Ricca, G. Della, Dittongo, S., Lanceri, L., Pompili, A., Poropat, P., Rashevskaia, I., Vuagnin, G., Burke, S., Callahan, D., Campagnari, C., Dahmes, B., Hale, D., Hart, P., Kuznetsova, N., Kyre, S., Levy, S., Long, O., May, J., Mazur, M., Richman, J., Verkerke, W., Witherell, M., Beringer, J., Eisner, A.M., Frey, A., Grillo, A.A., Grothe, M., Johnson, R.P., Kroeger, W., Lockman, W.S., Pulliam, T., Rowe, W., Schmitz, R.E., Seiden, A., Spencer, E.N., Turri, M., Walkoviak, W., Wilder, M., Wilson, M., Charles, E., Elmer, P., Nielsen, J., Orejudos, W., Scott, I., Zobernig, H., and Laplace, S.

Subjects
Radiation -- Measurement, Radiation warning systems -- Evaluation, Business, Electronics, Electronics and electrical industries
Abstract

The silicon-vertex tracker (SVT) for the BaBar Experiment at the PEP-II Asymmetric B Factory at Stanford Linear Accelerator Center (SLAC), is a five-layer double-sided ac-coupled silicon-microstrip detector. It is a crucial element for the precise measurement of the decay position of B mesons, satisfying the severe constraints imposed by the accelerator design, in terms of geometry of the interaction region and conditions of operation. In the following paper, the SVT performance is described. Radiation issues are discussed and the results of different tests aimed to study the decrease in the SVT performance due to radiation damage are presented. The alignment procedure is described, and a few BaBar physics results are presented as examples of the SVT capabilities to reconstruct decay vertices with good resolution and efficiency. Index Terms--Silicon radiation detectors.

Published
2002

50. Hydrogen-poor superluminous stellar explosions

Author

Quimby, R. M., Kulkarni, S. R., Kasliwal, M. M., Gal-Yam, A., Arcavi, I., Sullivan, M., Nugent, P., Thomas, R., Howell, D. A., Nakar, E., Bildsten, L., Theissen, C., Law, N. M., Dekany, R., Rahmer, G., Hale, D., Smith, R., Ofek, E. O., Zolkower, J., Velur, V., Walters, R., Henning, J., Bui, K., McKenna, D., Poznanski, D., Cenko, S. B., and Levitan, D.

Published
2011
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