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  • Valtchanov, I.; Hopwood, R.; Bendo, G.; Benson, C.; Conversi, L.; Fulton, T.; Griffin, M. J.; Joubaud, T.; Lim, T.; Lu, N.; Marchili, N.; Makiwa, G.; Meyer, R. A.; Naylor, D. A.; North, C.; Papageorgiou, A.; Pearson, C.; Polehampton, E. T.; Scott, J.; Schulz, B.; Spencer, L. D.; van der Wiel, M. H. D.; Wu, R. (Oxford University PressArts and ScienceDepartment of Physics and AstronomyEuropean Space Astronomy Centre (Spain)Imperial College LondonUniversity of ManchesterUniversity of LethbridgeBlue Sky SpectroscopyCardiff UniversityRutherford Appleton LaboratoryUniversidad de ChileIAPS-INAFEcole Polytechnique Fédérale de LausanneThe Open UniversityUniversity of OxfordCalifornia Institute of TechnologyASTRON, the Netherlands Institute for Radio AstronomySorbonne Universitéshttps://doi.org/10.1093/mnras/stx3178, 2017)
    We describe an update to the Herschel-Spectral and Photometric Imaging Receiver (SPIRE) Fourier-transform spectrometer (FTS) calibration for extended sources, which incorporates a correction for the frequency-dependent ...
  • Makiwa, G.; Naylor, David A.; van der Wiel, M. H. D.; Ward-Thompson, D.; Kirk, J. M.; Eyres, S.; Abergel, A.; Köhler, M. (Oxford University PressArts and ScienceDepartment of Physics and AstronomyUniversity of LethbridgeUniversity of CopenhagenUniversity of Central LancashireUniversité Paris SudCNRSQueen Mary University of Londonhttps://doi.org/10.1093/mnras/stw428, 2016)
    Dust grains play a key role in the physics of star-forming regions, even though they constitute only ∼1 per cent of the mass of the interstellar medium. The derivation of accurate dust parameters such as temperature (Td), ...
  • van der Wiel, M. H. D.; Naylor, David A.; Kamp, I.; Ménard, F.; Thi, W.-F.; Woitke, P.; Olofsson, G.; Pontoppidan, K. M.; Di Francesco, J.; Glauser, A. M.; Greaves, J. S.; Ivison, R. J. (Oxford University PressArts and ScienceDepartment of Physics and AstronomyUniversity of LethbridgeUniversity of GroningenCNRSUniversité Grenoble AlpesUniversity of St. AndrewsStockholm UniversitySpace Telescope Science InstituteNational Research Council CanadaUniversity of VictoriaETH ZurichEuropean Southern ObservatoryUniversity of Edinburghhttps://doi.org/10.1093/mnras/stu1462, 2014)
    Molecular gas constitutes the dominant mass component of protoplanetary discs. To date, these sources have not been studied comprehensively at the longest far-infrared and shortest submillimetre wavelengths. This paper ...
  • Hopwood, R.; Polehampton, E. T.; Valtchanov, I.; Swinyard, B. M.; Fulton, T.; Lu, N.; Marchili, N.; van der Wiel, M. H. D.; Benielli, D.; Imhof, P.; Baluteau, J.-P.; Pearson, C.; Clements, D. L.; Griffin, M. J.; Lim, T. L.; Makiwa, G.; Naylor, David A.; Noble, G.; Puga, E.; Spencer, L. D. (Oxford University PressArts and ScienceDepartment of Physics and AstronomyImperial College LondonRutherford Appleton LaboratoryUniversity of LethbridgeHerschel Science CentreUniversity College LondonNASA Herschel Science CentreIAPS-INAFUniversity of CopenhagenUniversité d'Aix-MarseilleBlue Sky SpectroscopyThe Open UniversityUniversity of OxfordCardiff UniversityUniversity of British Columbiahttps://doi.org/10.1093/mnras/stv353, 2015)
    A systematic programme of calibration observations was carried out to monitor the performance of the Spectral and Photometric Imaging REceiver (SPIRE) Fourier Transform Spectrometer (FTS) instrument on board the Herschel ...
  • Fulton, T.; Naylor, David A.; Polehampton, E. T.; Valtchanov, I.; Hopwood, R.; Lu, N.; Baluteau, J.-P.; Mainetti, G.; Pearson, C.; Papageorgiou, A.; Guest, S.; Zhang, L.; Imhof, P.; Swinyard, B. M.; Griffin, M. J.; Lim, T. L. (Oxford University PressArts and ScienceDepartment of Physics and AstronomyUniversity of LethbridgeBlue Sky SpectroscopyRutherford Appleton LaboratoryHerschel Science CentreImperial College LondonChinese Academy of SciencesNASA Herschel Science CentreUniversité d'Aix-MarseilleCardiff UniversityUniversity College Londonhttps://doi.org/10.1093/mnras/stw343, 2016)
    We present the data processing pipeline to generate calibrated data products from the Spectral and Photometric Imaging Receiver (SPIRE) imaging Fourier Transform Spectrometer on the Herschel Space Observatory. The pipeline ...
  • Faizal, Mir; Khalil, Mohammed M.; Das, Saurya (SpringerOpenArts and ScienceDepartment of Physics and AstronomyUniversity of WaterlooAlexandria UniversityUniversity of Lethbridgehttps://doi.org/10.1140/epjc/s10052-016-3884-4, 2016)
    Motivated by the Generalized Uncertainty Principle, covariance, and a minimum measurable time, we propose a deformation of the Heisenberg algebra and show that this leads to corrections to all quantum mechanical systems. ...
  • Deb, Soumen; Das, Saurya; Vagenas, Elias C. (ElsevierArts and ScienceDepartment of Physics & AstronomyUniversity of LethbridgeKuwait University, 2016)
    Quantum gravity effects modify the Heisenberg's uncertainty principle to a generalized uncertainty principle (GUP). Earlier work showed that the GUP-induced corrections to the Schrödinger equation, when applied to a ...
  • Bernard-Salas, J.; Habart, E.; Arab, H.; Abergel, A.; Dartois, E.; Martin, P.; Bontemps, S.; Joblin, C.; White, G. J.; Bernard, J.-P.; Naylor, David A. (EDP SciencesArts and ScienceDepartment of Physics & AstronomyInstitut d'Astrophysique SpatialeCanadian Institute for Theoretical AstrophysicsLaboratoire d'Astrophysique de BordeauxUniversité de ToulouseIRAPOpen UniversityRutherford Appleton LaboratoryUniversity of Lethbridge10.1051/0004-6361/201118083, 2012)
    Context. The energetics in photo-dissociation regions (PDRs) are mainly regulated by the balance between the heating from the photo-electric effect acting on dust grains, and the cooling via the copious emission of photons ...
  • van der Wiel, M. H. D.; Naylor, David A.; Makiwa, Gibion; Satt, M.; Abergel, A. (EDP SciencesArts and ScienceDepartment of Physics & AstronomyUniversity of CopenhagenUniversity of LethbridgeUniversity of RomeUniversité Paris-Saclay10.1051/0004-6361/201628512, 2016)
    Context. The HF molecule has been proposed as a sensitive tracer of diffuse interstellar gas, while at higher densities its abundance could be influenced heavily by freeze-out onto dust grains. Aims. We investigate the spatial ...
  • Das, Saurya; Majumdar, Parthasarathi (American Physical SocietyInstitute of Mathematical Scienceshttps://doi.org/10.1103/PhysRevLett.72.2524, 1994)
    The amplitude for the scattering of a point magnetic monopole and a point charge, at center-of- mass energies much larger than the masses of the particles, and in the limit of low momentum transfer, is shown to be ...
  • Das, Saurya; Majumdar, Parthasarathi (American Physical SocietyInstitute of Mathematical SciencesInternational Centre for Theoretical Physicshttps://doi.org/10.1103/PhysRevD.51.5664, 1995)
    The scattering of pointlike particles at a very large center-of-mass energies and fixed low momentum transfers, occurring due to both their electromagnetic and gravitational interactions, is reexamined in the particular ...
  • Das, Saurya; Majumdar, Parthasarathi (Elsevier BV North HollandInstitute of Mathematical Sciences (India)International Centre for Theoretical Physics, 1995)
    We consider possible mixing of electromagnetic and gravitational shock waves, in the Planckian energy scattering of point particles in Minkowski space, By boosting a Reissner-Nordstriim black hole solution to the velocity ...
  • Das, Saurya; Majumdar, Parthasarathi (American Physical SocietyInstitute of Mathematical Sciences (India)https://doi.org/10.1103/PhysRevD.55.2090, 1997)
    Approximating light charged pointlike particles in terms of ~nonextremal! dilatonic black holes is shown to lead to certain pathologies in Planckian scattering in the eikonal approximation, which are traced to the presence ...
  • Das, Saurya; Majumdar, Parthasarathi (Indian Academy of SciencesInstitute of Mathematical Sciences (India)https://www.ias.ac.in/article/fulltext/pram/051/03-04/0413-0419, 1998)
    We discuss an approach to compute two-particle scattering amplitudes for spinless light particles colliding at Planckian centre-of-mass energies, with increasing momentum transfer away from the eikonal limit. The leading ...
  • Das, Saurya; Dasgupta, Arundhati; Sarkar, Tapobrata (American Physical SocietyArts and ScienceInstitute of Mathematical Sciences (India)https://doi.org/10.1103/PhysRevD.55.7693, 1997)
    We study the emission of scalar particles from a class of near-extremal five-dimensional black holes and the corresponding D-brane configuration at high energies. We show that the distribution functions and the black hole ...
  • Das, Saurya; Dasgupta, Arundhati; Ramadevi, P.; Sarkar, Tapobrata (Elsevier BV North HollandInstitute of Mathematical Sciences (India)International Centre for Theoretical PhysicsTata Institute of Fundamental Research, 1988)
    We consider the gravitational scattering of point particles in four dimensions, at Planckian centre of mass energy and low momentum transfer, or the eikonal approximation. The scattering amplitude can be exactly computed ...
  • Das, Saurya; Dasgupta, Arundhati (SISSAPennsylvania State UniversityInstitute of Mathematical Sciences (India), 1999)
    We study the emission rates of scalar, spinor and vector particles from a 5 dimensional black hole for arbitrary partial waves. The solution is lifted to 6 dimensions, and the near horizon BTZ S3 geometry of the black ...
  • Das, Saurya; Kaul, Romesh K.; Majumdar, Parthasarathi (American Institute of PhysicsPennsylvania State UniversityThe Institute of Mathematical Sciences (India)https://doi.org/10.1103/PhysRevD.63.044019, 2001)
    A new entropy bound, tighter than the standard holographic bound due to Bekenstein, is derived for spacetimes with nonrotating isolated horizons from the quantum geometry approach, in which the horizon is described by ...
  • Das, Saurya; Ghosh, Amit; Mitra, P. (American Physical SocietyPennsylvania State UniversitySaha Institute of Nuclear Physics (Kolkata, India)https://doi.org/10.1103/PhysRevD.63.024023, 2000)
    The statistical entropy of a Schwarzschild black string in five dimensions is obtained by counting the black string states which form a representation of the near-horizon conformal symmetry with a central charge. ...
  • Das, Saurya; Mann, Robert B. (SISSAPennsylvania State UniversityUniversity of Waterloohttp://iopscience.iop.org/1126-6708/2000/08/033, 2000)
    We compute the conserved charges for Kerr anti-de Sitter spacetimes in various dimensions using the conformal and the counterterm prescriptions. We show that the conserved charge corresponding to the global timelike ...

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