G. Perumpilly
A5062605960- Neutrino Physics Research
- Particle physics theoretical and experimental studies
- Dark Matter and Cosmic Phenomena
- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Particle Detector Development and Performance
- Astrophysics and Cosmic Phenomena
- Radiation Detection and Scintillator Technologies
- Astro and Planetary Science
- Atomic and Subatomic Physics Research
- Magnetic confinement fusion research
- Superconducting Materials and Applications
- Gamma-ray bursts and supernovae
- Particle accelerators and beam dynamics
- Fusion materials and technologies
- Engineering Applied Research
- Muon and positron interactions and applications
- Medical Imaging Techniques and Applications
- Parallel Computing and Optimization Techniques
- Advanced Semiconductor Detectors and Materials
- Advanced Data Storage Technologies
- Radioactivity and Radon Measurements
- Real-time simulation and control systems
- Nuclear physics research studies
Rensselaer Polytechnic Institute
2019
University of South Dakota
2010-2018
University of Chicago
2014-2018
Fermi National Accelerator Laboratory
2017
University of North Carolina at Chapel Hill
2015
Center for Astrophysics Harvard & Smithsonian
2010-2012
The coherent elastic scattering of neutrinos off nuclei has eluded detection for four decades, even though its predicted cross section is by far the largest all low-energy neutrino couplings. This mode interaction offers new opportunities to study properties and leads a miniaturization detector size, with potential technological applications. We observed this process at 6.7σ confidence level, using low-background, 14.6-kilogram CsI[Na] scintillator exposed emissions from Spallation Neutron...
We report the discovery of HAT-P-16b, a transiting extrasolar planet orbiting V = 10.8 mag F8 dwarf GSC 2792-01700, with period P 2.775960 +- 0.000003 d, transit epoch Tc 2455027.59293 0.00031 (BJD), and duration 0.1276 0.0013 d. The host star has mass 1.22 0.04 Msun, radius 1.24 0.05 Rsun, effective temperature 6158 +-80 K, metallicity [Fe/H] +0.17 0.08. planetary companion 4.193 0.094 MJ, 1.289 0.066 RJ yielding mean density 2.42 0.35 g/cm3. Comparing these observed characteristics recent...
The Majorana Collaboration is operating an array of high purity Ge detectors to search for neutrinoless double-β decay in ^{76}Ge. Demonstrator comprises 44.1 kg (29.7 enriched ^{76}Ge) split between two modules contained a low background shield at the Sanford Underground Research Facility Lead, South Dakota. Here we present results from data taken during construction, commissioning, and start full operations. We achieve unprecedented energy resolution 2.5 keV FWHM Q_{ββ} very with no...
We present multi-band optical photometry of 94 spectroscopically confirmed Type Ia supernovae (SNe Ia) in the redshift range 0.0055–0.073, obtained between 2006 and 2011. There are a total 5522 light-curve points. show that our natural-system SN has precision ≲ 0.03 mag BVr'i', 0.06 u', 0.07 U for points brighter than 17.5 estimate it systematic uncertainty 0.014, 0.010, 0.012, 0.046, 0.073 BVr'i'u'U, respectively. Comparisons standard-system with published light curves comparison stars...
We report the discovery of four relatively massive (2–7 MJ) transiting extrasolar planets. HAT-P-20b orbits moderately bright V = 11.339 K3 dwarf star GSC 1910-00239 on a circular orbit, with period P 2.875317 ± 0.000004 days, transit epoch Tc 2455080.92661 0.00021 (BJDUTC), and duration 0.0770 0.0008 days. The host has mass 0.76 0.03 M☉, radius 0.69 0.02 R☉, effective temperature 4595 80 K, metallicity [Fe/H] +0.35 0.08. planetary companion 7.246 0.187 MJ 0.867 0.033 RJ yielding mean...
We report the discovery of HAT-P-26b, a transiting extrasolar planet orbiting moderately bright V=11.744 K1 dwarf star GSC 0320-01027, with period P = 4.234516 +- 0.000015 d, transit epoch Tc 2455304.65122 0.00035 (BJD), and duration 0.1023 0.0010 d. The host has mass 0.82 0.03 Msun, radius 0.79 + 0.10 - 0.04 Rsun, effective temperature 5079 88 K, metallicity [Fe/H] -0.04 0.08. planetary companion 0.059 0.007 MJ, 0.565 0.072 0.032 RJ yielding mean density 0.40 g cm-3. HAT-P-26b is fourth...
We report the discovery of HAT-P-27b, an exoplanet transiting moderately bright G8 dwarf star GSC 0333-00351 (V = 12.214). The orbital period is 3.039586 ± 0.000012 days, reference epoch transit 2455186.01879 0.00054 (BJD), and duration 0.0705 0.0019 days. host with its effective temperature 5300 90 K somewhat cooler than Sun more metal-rich a metallicity +0.29 0.10. Its mass 0.94 0.04 M☉ radius 0.90+0.05− R☉. For planetary companion we determine 0.660 0.033 MJ 1.038+0.077− 0.058 RJ. 30...
We report the discovery of two new transiting extrasolar planets. HAT-P-18b orbits V = 12.759 K2 dwarf star GSC 2594−00646, with a period P 5.508023 ± 0.000006 days, transit epoch Tc 2454715.02174 0.00020 (BJD), and duration 0.1131 0.0009 days. The host has mass 0.77 0.03 M☉, radius 0.75 0.04 R☉, effective temperature 4803 80 K, metallicity [Fe/H] +0.10 0.08. planetary companion 0.197 0.013 MJ 0.995 0.052 RJ, yielding mean density 0.25 g cm−3. HAT-P-19b 12.901 K1 2283−00589, 4.008778...
We report the discovery of HAT-P-17b,c, a multi-planet system with an inner transiting planet in short-period, eccentric orbit and outer 4.4 yr, nearly circular orbit. The planet, HAT-P-17b, transits bright V = 10.54 early K dwarf star GSC 2717-00417, orbital period P 10.338523 ± 0.000009 days, eccentricity e 0.342 0.006, transit epoch Tc 2454801.16943 0.00020 (BJD: barycentric Julian dates throughout paper are calculated from Coordinated Universal Time (UTC)), duration 0.1690 0.0009 days....
We report the discovery of HAT-P-24b, a transiting extrasolar planet orbiting moderately bright V = 11.818 F8 dwarf star GSC 0774−01441, with period P 3.3552464 ± 0.0000071 days, transit epoch Tc 2455216.97669 0.00024 (BJD)11, and duration 3.653 0.025 hr. The host has mass 1.191 0.042 M☉, radius 1.317 0.068 R☉, effective temperature 6373 80 K, low metallicity [Fe/H] -0.16 0.08. planetary companion 0.681 0.031 MJ 1.243 0.072 RJ yielding mean density 0.439 0.069 g cm-3. By repeating our global...
We report the discovery of HAT-P-25b, a transiting extrasolar planet orbiting V = 13.19 G5 dwarf star GSC 1788-01237, with period P 3.652836 ± 0.000019 days, transit epoch Tc 2455176.85173 0.00047 (BJD—barycentric Julian dates throughout paper are calculated from Coordinated Universal Time, UTC), and duration 0.1174 0.0017 days. The host has mass 1.01 0.03 M☉, radius 0.96+0.05− 0.04 R☉, effective temperature 5500 80 K, metallicity [Fe/H] +0.31 0.08. planetary companion 0.567 0.022 MJ...
The observation of neutrino less double-beta decay would show that neutrinos are Majorana particles and provide information on mass. Attaining sensitivities for masses in the inverted hierarchy region requires large, tonne scale detectors with extremely low backgrounds, at level 10−3 counts keV−1 t−1 y−1 or lower signal. MAJORANA collaboration is constructing DEMONSTRATOR, an array consisting 40 kg p-type point contact germanium detectors, least half which will be enriched to 86% 76Ge....
The direct search for dark matter is entering a period of increased sensitivity to the hypothetical Weakly Interacting Massive Particle (WIMP). One such technology that being examined scintillation only noble liquid experiment, MiniCLEAN. MiniCLEAN utilizes over 500 kg cryogen detect nuclear recoils from WIMP and serves as demonstration future detector order 50 100 tonnes. interchangeable between argon neon study A2 dependence potential signal examine backgrounds. unique modular design with...
The observation of neutrinoless double-beta decay would resolve the Majorana nature neutrino and could provide information on absolute scale mass. initial phase experiment, known as Demonstrator, will house 40 kg Ge in an ultra-low background shielded environment at 4850' level Sanford Underground Laboratory Lead, SD. objective Demonstrator is to determine whether a future 1-tonne experiment can achieve goal one count per tonne-year narrow region interest around 76Ge peak.
A brief review of the history and neutrino physics double beta decay is given. description MAJORANA DEMONSTRATOR research development program including background reduction techniques presented in some detail. The application point contact (PC) detectors to experiment discussed, effectiveness pulse shape analysis. predicted sensitivity a PC detector array enriched 86% 76Ge
The Majorana Demonstrator is an array of natural and enriched high purity germanium detectors that will search for the neutrinoless double-beta decay Germanium-76 perform a weakly interacting massive particles with masses below 10 GeV. To reach background rate goal in region interest 4 counts/keV/t/y, DEMONSTRATOR utilize number reduction strategies, including time-correlated event cut 68Ge requires sub-keV energy threshold. This low threshold allows to extend its physics include light...
This paper provides a comprehensive review of the TRANSP code, sophisticated tool for interpretive and predictive analysis tokamak plasmas, detailing its major capabilities features. It describes equations particle, power, momentum balance analysis, as well poloidal field diffusion equations. The outlines spatial time grids used in details equilibrium assumptions solvers. Various models heating current drive, including updates to NUBEAM model, are discussed. handling large-scale events such...