Brian D. Fields

CERN, Genève, Geneva, Switzerland

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Publications (132)506.09 Total impact

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    ABSTRACT: We studied previously the impact on light-element abundances of gravitinos decaying during or after Big-Bang nucleosynthesis (BBN). We found regions of the gravitino mass m_{3/2} and abundance zeta_{3/2} plane where its decays could reconcile the calculated abundance of Li7 with observation without perturbing the other light-element abundances unacceptably. Here we revisit this issue in light of LHC measurements of the Higgs mass and constraints on supersymmetric model parameters, as well as updates in the astrophysical measurements of light-element abundances. In addition to the constrained minimal supersymmetric extension of the Standard Model with universal soft supersymmetry-breaking masses at the GUT scale (the CMSSM) studied previously, we also study models with universality imposed below the GUT scale and models with non-universal Higgs masses (NUHM1). We calculate the total likelihood function for the light-element abundances, taking into account the observational uncertainties. We find that gravitino decays provide a robust solution to the cosmological Li7 problem along strips in the (m_{3/2}, zeta_{3/2}) plane along which the abundances of deuterium, He4 and Li7 may be fit with chi^2_min < 3, compared with chi^2 ~ 34 if the effects of gravitino decays are unimportant. The minimum of the likelihood function is reduced to chi^2 < 2 when the uncertainty on D/H is relaxed and < 1 when the lithium abundance is taken from globular cluster data.
    Journal of Cosmology and Astroparticle Physics 03/2013; 2013(05). · 6.04 Impact Factor
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    ABSTRACT: The primordial abundances of light elements produced in the standard theory of Big Bang nucleosynthesis (BBN) depend only on the cosmic ratio of baryons to photons, a quantity inferred from observations of the microwave background. The predicted primordial (7)Li abundance is four times that measured in the atmospheres of Galactic halo stars. This discrepancy could be caused by modification of surface lithium abundances during the stars' lifetimes or by physics beyond the Standard Model that affects early nucleosynthesis. The lithium abundance of low-metallicity gas provides an alternative constraint on the primordial abundance and cosmic evolution of lithium that is not susceptible to the in situ modifications that may affect stellar atmospheres. Here we report observations of interstellar (7)Li in the low-metallicity gas of the Small Magellanic Cloud, a nearby galaxy with a quarter the Sun's metallicity. The present-day (7)Li abundance of the Small Magellanic Cloud is nearly equal to the BBN predictions, severely constraining the amount of possible subsequent enrichment of the gas by stellar and cosmic-ray nucleosynthesis. Our measurements can be reconciled with standard BBN with an extremely fine-tuned depletion of stellar Li with metallicity. They are also consistent with non-standard BBN.
    Nature 09/2012; 489(7414):121-3. · 38.60 Impact Factor
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    ABSTRACT: We consider the effects of metastable charged sparticles on Big-Bang Nucleosynthesis (BBN), including bound-state reaction rates and chemical effects. We make a new analysis of the bound states of negatively-charged massive particles with the light nuclei most prominent in BBN, and present a new code to track their abundances, paying particular attention to that of Li7. Assuming, as an example, that the gravitino is the lightest supersymmetric particle (LSP), and that the lighter stau slepton, stau_1, is the metastable next-to-lightest sparticle within the constrained minimal supersymmetric extension of the Standard Model (CMSSM), we analyze the possible effects on the standard BBN abundances of stau_1 bound states and decays for representative values of the gravitino mass. Taking into account the constraint on the CMSSM parameter space imposed by the discovery of the Higgs boson at the LHC, we delineate regions in which the fit to the measured light-element abundances is as good as in standard BBN. We also identify regions of the CMSSM parameter space in which the bound state properties, chemistry and decays of metastable charged sparticles can solve the cosmological Li7 problem.
    Journal of Cosmology and Astroparticle Physics 09/2012; · 6.04 Impact Factor
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    Nachiketa Chakraborty, Brian D. Fields
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    ABSTRACT: Fermi has resolved several star-forming galaxies, but the vast majority of the star-forming universe is unresolved and thus contributes to the extragalactic gamma ray background (EGB). Here, we calculate the contribution from star-forming galaxies to the EGB in the Fermi range from 100 MeV to 100 GeV, due to inverse-Compton (IC) scattering of the interstellar photon field by cosmic-ray electrons. We first construct a one-zone model for a single star-forming galaxy, assuming supernovae power the acceleration of cosmic rays. The same IC interactions leading to gamma rays also substantially contribute to the energy loss of the high-energy cosmic-ray electrons. Consequently, a galaxy's IC emission is determined by the relative importance of IC losses in the cosmic-ray electron energy budget ("partial calorimetry"). We use our template for galactic IC luminosity to find the cosmological contribution of star-forming galaxies to the EGB. For all of our models, we find the IC EGB contribution is almost an order of magnitude less than the peak of the emission due to cosmic-ray ion interactions (mostly pionic p_cr p_ism \rightarrow \pi_0 \rightarrow \gamma \gamma); even at the highest Fermi energies, IC is subdominant. Moreover, the flatter IC spectrum increases the high-energy signal of the pionic+IC sum, bringing it into better agreement with the EGB spectral index observed by Fermi . Partial calorimetry ensures that the overall IC signal is well constrained, with only modest uncertainties in the amplitude and spectral shape for plausible model choices. Partial calorimetry of cosmic-ray electrons should hold true in both normal and starburst galaxies, and thus we include starbursts in our calculation. We conclude with a brief discussion on how the pionic spectral feature and other methods can be used to measure the star-forming component of the EGB.
    The Astrophysical Journal 06/2012; 773(2). · 6.73 Impact Factor
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    Brian D. Fields
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    ABSTRACT: Big-bang nucleosynthesis (BBN) theory, together with the precise WMAP cosmic baryon density, makes tight predictions for the abundances of the lightest elements. Deuterium and 4He measurements agree well with expectations, but 7Li observations lie a factor 3-4 below the BBN+WMAP prediction. This 4-5\sigma\ mismatch constitutes the cosmic "lithium problem," with disparate solutions possible. (1) Astrophysical systematics in the observations could exist but are increasingly constrained. (2) Nuclear physics experiments provide a wealth of well-measured cross-section data, but 7Be destruction could be enhanced by unknown or poorly-measured resonances, such as 7Be + 3He -> 10C^* -> p + 9B. (3) Physics beyond the Standard Model can alter the 7Li abundance, though D and 4He must remain unperturbed; we discuss such scenarios, highlighting decaying Supersymmetric particles and time-varying fundamental constants. Present and planned experiments could reveal which (if any) of these is the solution to the problem.
    Annual Review of Nuclear and Particle Science 03/2012; 61. · 7.40 Impact Factor
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    Amy Lien, Brian D. Fields
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    ABSTRACT: The origin of the diffuse extragalactic gamma-ray background (EGB) has been intensively studied but remains unsettled. Current popular source candidates include unresolved star-forming galaxies, starburst galaxies, and blazars. In this paper we calculate the EGB contribution from the interactions of cosmic rays accelerated by Type Ia supernovae (SNe), extending earlier work which only included core-collapse SNe. We consider Type Ia events in star-forming galaxies, but also in quiescent galaxies that lack star formation. For star-forming galaxies, consistently including Type Ia events makes little change to the star-forming EGB prediction, so long as both SN types have the same cosmic-ray acceleration efficiencies in star-forming galaxies. Thus, our updated EGB estimate continues to show that star-forming galaxies can represent a substantial portion of the signal measured by Fermi. For quiescent galaxies, conversely, we find a wide range of possibilities for the EGB contribution. The dominant uncertainty we investigated comes from the mass in hot gas, which provides targets for cosmic rays; total gas masses are as yet poorly known, particularly at larger radii. Additionally, the EGB estimation is very sensitive to the cosmic-ray acceleration efficiency and confinement, especially in quiescent galaxies. In the most optimistic allowed scenarios, quiescent galaxies can be an important source of the EGB. In this case, star-forming galaxies and quiescent galaxies together will dominate the EGB and leave little room for other contributions. If other sources, such as blazars, are found to have important contributions to the EGB, then either the gas mass or cosmic-ray content of quiescent galaxies must be significantly lower than in their star-forming counterparts. In any case, improved Fermi EGB measurements will provide important constraints on hot gas and cosmic rays in quiescent galaxies.
    The Astrophysical Journal 01/2012; 747(2). · 6.73 Impact Factor
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    ABSTRACT: Residual late-time dark matter particle annihilations during and after Big Bang Nucleosynthesis (BBN) may alter the predicted cosmological abundances of the light elements. Within the constrained minimal supersymmetric extension of the Standard Model (the CMSSM) with a neutralino LSP, we find negligible effects on the abundances of Deuterium, He3, He4 and Li7 predicted by homogeneous BBN, but potentially a large enhancement in the predicted abundance of Li6. This enhancement may be as much as two orders of magnitude in the focus-point WMAP strip and in the coannihilation and funnel regions for large tan beta for small m_{1/2}, and the effect is still significant at large m_{1/2}. However, the potential Li6 enhancement is negligible in the part of the coannihilation strip for tan beta = 10 that survives the latest LHC constraints. A similar enhancement of the \li6 abundance may also be found in a model with common, non-universal Higgs masses (the NUHM1).
    Physical review D: Particles and fields 09/2011; 84.
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    ABSTRACT: Radio properties of supernova outbursts remain poorly understood despite longstanding campaigns following events discovered at other wavelengths. After ~ 30 years of observations, only ~ 50 supernovae have been detected at radio wavelengths, none of which are Type Ia. Even the most radio-loud events are ~ 10^4 fainter in the radio than in the optical; to date, such intrinsically dim objects have only been visible in the very local universe. The detection and study of radio supernovae (RSNe) will be fundamentally altered and dramatically improved as the next generation of radio telescopes comes online, including EVLA, ASKAP, and MeerKAT, and culminating in the Square Kilometer Array (SKA); the latter should be > 50 times more sensitive than present facilities. SKA can repeatedly scan large (> 1 deg^2) areas of the sky, and thus will discover RSNe and other transient sources in a new, automatic, untargeted, and unbiased way. We estimate SKA will be able to detect core-collapse RSNe out to redshift z ~ 5, with an all-redshift rate ~ 620 events yr^-1 deg^-2, assuming a survey sensitivity of 50 nJy and radio lightcurves like those of SN 1993J. Hence SKA should provide a complete core-collapse RSN sample that is sufficient for statistical studies of radio properties of core-collapse supernovae. EVLA should find ~ 160 events yr^-1 deg^-2 out to redshift z ~ 3, and other SKA precursors should have similar detection rates. We also provided recommendations of the survey strategy to maximize the RSN detections of SKA. This new radio core-collapse supernovae sample will complement the detections from the optical searches, such as the LSST, and together provide crucial information on massive star evolution, supernova physics, and the circumstellar medium, out to high redshift. Additionally, SKA may yield the first radio Type Ia detection via follow-up of nearby events discovered at other wavelengths.
    The Astrophysical Journal 07/2011; 740. · 6.73 Impact Factor
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    D. N. Friedel, Athol Kemball, Brian D. Fields
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    ABSTRACT: We have conducted Combined Array for Research in Millimeter-wave Astronomy (CARMA) observations of LiH, in absorption, toward three quasars. These quasars, B0218+357, PKS1830-211, and PKS0201+113, have redshifts of z = 0.685 - 3.387$, and shift the LiH J=1-0 transition to the 1 mm and 3mm wavelength bands, where atmospheric absorption is sharply reduced from that predominating near the rest frequency of 443 GHz. We report a 3$\sigma$ detection of LiH toward B0218+357 with a column density of 1.4x10^{12} cm^{-2} and place an upper limit on the ^6Li/^7Li ratio of <0.16. LiH was not detected toward any other source.
    The Astrophysical Journal 06/2011; 738. · 6.73 Impact Factor
  • Themis Athanassiadou, B.D. Fields
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    ABSTRACT: We investigate the method by which nearby supernovae – within a few tens of pc of the solar system – can penetrate the solar system and deposit live radioactivities on earth. The radioactive isotopic signatures that could potentially leave an observable geological imprint are in the form of refractory metals; consequently, it is likely they would arrive in the form of supernova-produced dust grains. Such grains can penetrate into the solar system more easily than the bulk supernova plasma, which gets stalled and deflected near the solar system due to the solar wind plasma pressure. We therefore examine the motion of charged grains as they decouple from the supernova plasma and are influenced by the solar magnetic, radiation, and gravitational fields. We characterize the dust trajectories with analytical approximations which display the roles of grain size, initial velocity, and surface voltage. These results are verified with full numerical simulations for wide ranges of dust properties. We find that supernova dust grains traverse the inner solar system nearly undeflected, if the incoming grain velocity – which we take to be that of the incident supernova remnant – is comparable to the solar wind speeds and much larger than the escape velocity at 1 AU. Consequently, the dust penetration to 1 AU has essentially 100% transmission probability and the dust capture onto the earth should have a geometric cross section. Our results cast in a new light the terrestrial deposition of radioisotopes from nearby supernovae in the geological past. For explosions beyond ∼10 pc from earth, dust grains can still deliver supernova ejecta to earth, and thus the amount of supernova material deposited is set by the efficiency of dust condensation and survival in supernovae. Turning the problem around, we use observations of live 60Fe in both deep-ocean and lunar samples to infer a conservative lower bound iron condensation efficiency of Mdust,Fe/Mtot,Fe ≳ 4 × 10−4 for the supernova which apparently produced these species 2–3 Myr ago.
    New Astronomy 01/2011; · 1.85 Impact Factor
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    ABSTRACT: A main science goal of LSST is to detect Type Ia supernovae, but the survey will also revolutionize our understanding of core-collapse events. LSST will observe 105 core-collapse supernovae per year out to z 1 and obtain the cosmic supernova rate by direct counting, in an unbiased way and with high statistics. Many science applications will therefore be feasible. Here, we discuss synergies with neutrino detectors and radio observations. The cumulative (anti)neutrino production from all core-collapse supernovae within our cosmic horizon gives rise to a diffuse supernova neutrino background (DSNB) which is on the verge of detectability. The observed flux depends on supernova physics, but also on the cosmic history of supernova explosions. The high precision measurement of the cosmic supernova rate will allow precise predictions of DSNB and make it a strong probe of optically invisible supernovae, which may be unseen either due to unexpected large dust obscuration in host galaxies, or because some core-collapse events proceed directly to black hole formation and fail to give an optical outburst. Another way to uncover optically invisible supernovae would be the next generation radio telescope, the Square Kilometer Array (SKA). SKA will be capable of unbiased synoptic searches over large fields of view with remarkable sensitivity and explode the radio core-collapse supernova inventory from the current number of several dozen in the local universe to 600 yr-1 deg-2 out to z 5. SKA will be complementary to LSST and together provide crucial information for dust evolution and star-formation at high redshift.
    01/2011;
  • Brian D. Fields, V. Pavlidou, T. Prodanovic
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    ABSTRACT: The origin of the extragalactic gamma-ray background is a pressing cosmological mystery. The Fermi Gamma-Ray Space Telescope has recently measured the intensity and spectrum of this background; both are substantially different from previous measurements. We present a novel calculation of the gamma-ray background from normal star-forming galaxies. Contrary to longstanding expectations, we find that numerous but individually faint normal galaxies may comprise the bulk of the Fermi signal, rather than rare but intrinsically bright active galaxies. This result has wide-ranging implications, including: the possibility to probe the cosmic star-formation history with gamma rays; the ability to infer the cosmological evolution of cosmic rays and galactic magnetic fields; and an increased likelihood to identify subdominant components from rare sources (e.g., dark matter annihilation).
    01/2011;
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    ABSTRACT: Observational and theoretical evidence suggests that high-energy Galactic cosmic rays are primarily accelerated by supernova remnants. If also true for low-energy cosmic rays, the ionization rate near a supernova remnant should be higher than in the general Galactic interstellar medium (ISM). We have searched for H+ 3 absorption features in six sight lines which pass through molecular material near IC 443—a well-studied case of a supernova remnant interacting with its surrounding molecular material—for the purpose of inferring the cosmic-ray ionization rate in the region. In two of the sight lines (toward ALS 8828 and HD 254577) we find large H+ 3 column densities, N(H+ 3) ≈ 3 × 1014 cm-2, and deduce ionization rates of ζ2 ≈ 2 × 10-15 s-1, about five times larger than inferred toward average diffuse molecular cloud sight lines. However, the 3σ upper limits found for the other four sight lines are consistent with typical Galactic values. This wide range of ionization rates is likely the result of particle acceleration and propagation effects, which predict that the cosmic-ray spectrum and thus ionization rate should vary in and around the remnant. While we cannot determine if the H+ 3 absorption arises in post-shock (interior) or pre-shock (exterior) gas, the large inferred ionization rates suggest that IC 443 is in fact accelerating a large population of low-energy cosmic rays. Still, it is unclear whether this population can propagate far enough into the ISM to account for the ionization rate inferred in diffuse Galactic sight lines. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. Based in part on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan.
    The Astrophysical Journal 12/2010; · 6.73 Impact Factor
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    ABSTRACT: We explore a nuclear physics resolution to the discrepancy between the predicted standard big-bang nucleosynthesis (BBN) abundance of 7Li and its observational determination in metal-poor stars. The theoretical 7Li abundance is 3-4 times greater than the observational values, assuming the baryon-to-photon ratio, eta_wmap, determined by WMAP. The 7Li problem could be resolved within the standard BBN picture if additional destruction of A=7 isotopes occurs due to new nuclear reaction channels or upward corrections to existing channels. This could be achieved via missed resonant nuclear reactions, which is the possibility we consider here. We find some potential candidate resonances which can solve the lithium problem and specify their required resonant energies and widths. For example, a 1^- or 2^- excited state of 10C sitting at approximately 15.0 MeV above its ground state with an effective width of order 10 keV could resolve the 7Li problem; the existence of this excited state needs experimental verification. Other examples using known states include 7Be+t \rightarrow 10B(18.80 MeV), and 7Be+d \rightarrow 9B(16.71 MeV). For all of these states, a large channel radius (a > 10 fm) is needed to give sufficiently large widths. Experimental determination of these reaction strengths is needed to rule out or confirm these nuclear physics solutions to the lithium problem.
    Physical review D: Particles and fields 11/2010; 83(6).
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    ABSTRACT: We explore the consequences of an early population of intermediate mass stars in the 2 - 8 M\odot range on cosmic chemical evolution. We discuss the implications of this population as it pertains to several cosmological and astrophysical observables. For example, some very metal-poor galactic stars show large enhancements of carbon, typical of the C-rich ejecta of low-mass stars but not of supernovae; moreover, halo star carbon and oxygen abundances show wide scatter, which imply a wide range of star-formation and nucleosynthetic histories contributed to the first generations of stars. Also, recent analyses of the 4He abundance in metal-poor extragalactic H II regions suggest an elevated abundance Yp \simeq 0.256 by mass, higher than the predicted result from big bang nucleosynthesis assuming the baryon density determined by WMAP, Yp = 0.249. Although there are large uncertainties in the observational determination of 4He, this offset may suggest a prompt initial enrichment of 4He in early metal-poor structures. We also discuss the effect of intermediate mass stars on global cosmic evolution, the reionization of the Universe, the density of white dwarfs, as well as SNII and SNIa rates at high redshift. We also comment on the early astration of D and 7Li. We conclude that if intermediate mass stars are to be associated with Population III stars, their relevance is limited (primarily from observed abundance patterns) to low mass structures involving a limited fraction of the total baryon content of the Universe. Comment: Submitted to MNRAS
    Monthly Notices of the Royal Astronomical Society 10/2010; · 5.52 Impact Factor
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    Tijana Prodanović, Gary Steigman, Brian D. Fields
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    ABSTRACT: As the Galaxy evolves, the abundance of deuterium in the interstellar medium (ISM) decreases from its primordial value: deuterium is ‘astrated’. The deuterium astration factor fD, the ratio of the primordial D abundance (the D to H ratio by number) to the ISM D abundance, is determined by the competition between stellar destruction and infall, providing a constraint on models of the chemical evolution of the Galaxy. Although conventional wisdom suggests that the local ISM (i.e. within ∼1–2 kpc of the Sun) should be well mixed and homogenized on time-scales short compared to the chemical evolution time-scale, the data reveal gas-phase variations in the deuterium, iron and other metal abundances as large as factors of ∼4–5 or more, complicating the estimate of the ‘true’ ISM D abundance and of the deuterium astration factor. Here, assuming that the variations in the observationally inferred ISM D abundances result entirely from the depletion of D on to dust, rather than from unmixed accretion of nearly primordial material, a model-independent, Bayesian approach is used to determine the undepleted abundance of deuterium in the ISM (or a lower limit to it). We find the best estimate for the undepleted, ISM deuterium abundance to be (D/H)ISM≥ (2.0 ± 0.1) × 10−5. This result is used to provide an estimate of (or an upper bound to) the deuterium astration factor, fD≡ (D/H)P/(D/H)ISM≤ 1.4 ± 0.1.
    Monthly Notices of the Royal Astronomical Society 07/2010; 406(2):1108 - 1115. · 5.52 Impact Factor
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    ABSTRACT: We consider the effects of uncertainties in nuclear reaction rates on the cosmological constraints on the decays of unstable particles during or after Big-Bang nucleosynthesis (BBN). We identify the nuclear reactions due to non-thermal hadrons that are the most important in perturbing standard BBN, then quantify the uncertainties in these reactions and in the resulting light-element abundances. These results also indicate the key nuclear processes for which improved cross section data would allow different light-element abundances to be determined more accurately, thereby making possible more precise probes of BBN and evaluations of the cosmological constraints on unstable particles. Applying this analysis to models with unstable gravitinos decaying into neutralinos, we calculate the likelihood function for the light-element abundances measured currently, taking into account the current experimental errors in the determinations of the relevant nuclear reaction rates. We find a region of the gravitino mass and abundance in which the abundances of deuterium, He4 and Li7 may be fit with chi^2 = 5.5, compared with chi^2 = 31.7 if the effects of gravitino decays are unimportant. The best-fit solution is improved to chi^2 ~ 2.0 when the lithium abundance is taken from globular cluster data. Some such re-evaluation of the observed light-element abundances and/or nuclear reaction rates would be needed if this region of gravitino parameters is to provide a complete solution to the cosmological Li7 problem.
    Journal of Cosmology and Astroparticle Physics 07/2010; 10(10). · 6.04 Impact Factor
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    ABSTRACT: Our solar system appears to have received material from supernovae at least twice in its life: during its formation and 3 Myrs ago. We combine analysis of the latter event to constrain how supernova ejecta could have made it into the solar nebula.
    LPI Contributions. 04/2010;
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    ABSTRACT: The origin of the extragalactic gamma-ray background is a pressing cosmological mystery. The Fermi Gamma-Ray Space Telescope has recently measured the intensity and spectrum of this background; both are substantially different from previous measurements. This revision demands a re-evaluation of the sources for the cosmic signal. We present a novel calculation of the gamma-ray background from star-forming galaxies like our own. Contrary to longstanding expectations, we find that numerous but individually faint normal galaxies comprise the bulk of the Fermi signal, rather than rare but intrinsically bright active galaxies. The return of star-forming galaxies to dominate the extragalactic gamma-ray sky has wide-ranging implications, including: the possibility to probe cosmic star-formation history with gamma rays; the ability to infer the cosmological evolution of cosmic rays and galactic magnetic fields; and an increased likelihood to identify subdominant components from rare sources (e.g., dark matter clumps) through their large anisotropy. Comment: 19 pages, 1 figure.
    The Astrophysical Journal Letters 03/2010; · 6.35 Impact Factor
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    Amy Lien, Brian D. Fields, John F. Beacom
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    ABSTRACT: The cumulative (anti)neutrino production from all core-collapse supernovae within our cosmic horizon gives rise to the diffuse supernova neutrino background (DSNB), which is on the verge of detectability. The observed flux depends on supernova physics, but also on the cosmic history of supernova explosions; currently, the cosmic supernova rate introduces a substantial (+/-40%) uncertainty, largely through its absolute normalization. However, a new class of wide-field, repeated-scan (synoptic) optical sky surveys is coming online, and will map the sky in the time domain with unprecedented depth, completeness, and dynamic range. We show that these surveys will obtain the cosmic supernova rate by direct counting, in an unbiased way and with high statistics, and thus will allow for precise predictions of the DSNB. Upcoming sky surveys will substantially reduce the uncertainties in the DSNB source history to an anticipated +/-5% that is dominated by systematics, so that the observed high-energy flux thus will test supernova neutrino physics. The portion of the universe (z < 1) accessible to upcoming sky surveys includes the progenitors of a large fraction (~ 87%) of the expected 10-26 MeV DSNB event rate. We show that precision determination of the (optically detected) cosmic supernova history will also make the DSNB into a strong probe of an extra flux of neutrinos from optically invisible supernovae, which may be unseen either due to unexpected large dust obscuration in host galaxies, or because some core-collapse events proceed directly to black hole formation and fail to give an optical outburst. Comment: 11 pages, 6 figures
    Physical review D: Particles and fields 01/2010;

Publication Stats

3k Citations
506.09 Total Impact Points

Institutions

  • 1996–2013
    • CERN
      • Physics Department (PH)
      Genève, Geneva, Switzerland
  • 1998–2012
    • University of Illinois, Urbana-Champaign
      • • Department of Physics
      • • Department of Astronomy
      Urbana, Illinois, United States
    • University of Michigan
      • Department of Physics
      Ann Arbor, Michigan, United States
  • 2007–2009
    • University of Novi Sad
      • Department of Physics
      Novi Sad, VO, Serbia
  • 2006–2007
    • University of Chicago
      • Kavli Institute for Cosmological Physics
      Chicago, Illinois, United States
  • 1998–2003
    • University of Minnesota Duluth
      • Department of Physics
      Duluth, Minnesota, United States
  • 1995–1998
    • University of Notre Dame
      • Department of Physics
      South Bend, Indiana, United States
    • Institut d'astrophysique de Paris
      Lutetia Parisorum, Île-de-France, France