We expound in detail the physics reaches of an experimental set-up in which the proposed large magnetized iron detector at the India-based Neutrino Observatory (INO) would serve as the far detector for a so-called beta-beam. If this pure νe and/or over(ν, ̄)e beam is shot from some source location like CERN such that the source-detector distance L ≃ 7500 km, the impact of the CP phase δCP on the oscillation probability and associated parameter correlation and degeneracies are almost negligible. This "magical" beta-beam experiment would have unprecedented sensitivity to the neutrino mass hierarchy and θ13, two of the missing ingredients needed for our understanding of the neutrino sector. With Lorentz boost γ = 650 and irrespective of the true value of δCP, the neutrino mass hierarchy could be determined at 3σ C.L. if sin2 2 θ13 (true) &gt; 5.6 × 10-4 and we can expect an unambiguous signal for θ13 at 3σ C.L. if sin2 2 θ13 (true) &gt; 5.1 × 10-4 independent of the true neutrino mass hierarchy. © 2008 Elsevier B.V. All rights reserved.

S K AGARWALLA

S CHOUBEY

A RAYCHAUDHURI

Fulltext

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

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The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

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It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

Nuclear Physics B

We examine the reach of a Beta-beam experiment with two detectors at carefully chosen baselines for exploring neutrino mass parameters. Locating the source at CERN, the two detectors and baselines are: (a) a 50 kton iron calorimeter (ICAL) at a baseline of around 7150 km which is roughly the magic baseline, e.g., ICAL@INO, and (b) a 50 kton Totally Active Scintillator Detector at a distance of 730 km, e.g., at Gran Sasso. We choose 8B and 8Li source ions with a boost factor γ of 650 for the magic baseline while for the closer detector we consider 18Ne and 6He ions with a range of Lorentz boosts. We find that the locations of the two detectors complement each other leading to an exceptional high sensitivity. With γ = 650 for 8B/8Li and γ = 575 for 18Ne/6He and total luminosity corresponding to 5 × (1.1 × 1018) and 5 × (2.9 × 1018) useful ion decays in neutrino and antineutrino modes respectively, we find that the two-detector set-up can probe maximal CP violation and establish the neutrino mass ordering if sin2 2 θ13 is 1.4 × 10-4 and 2.7 × 10-4, respectively, or more. The sensitivity reach for sin2 2 θ13 itself is 5.5 × 10-4. With a factor of 10 higher luminosity, the corresponding sin2 2 θ13 reach of this set-up would be 1.8 × 10-5, 4.6 × 10-5 and 5.3 × 10-5 respectively for the above three performance indicators. CP violation can be discovered for 64% of the possible δCP values for sin2 2 θ13 ≥ 10-3 (≥ 8 × 10-5), for the standard luminosity (10 times enhanced luminosity). Comparable physics performance can be achieved in a set-up where data from CERN to INO@ICAL is combined with that from CERN to the Boulby mine in United Kingdom, a baseline of 1050 km. © 2008 Elsevier B.V. All rights reserved.

Exceptional sensitivity to neutrino parameters with a two-baseline Beta-beam set-up

We perform a comprehensive and detailed comparison of the physics reach of Beta-beam neutrino experiments between two pairs of plausible source ions, ( 8B, 8Li) and ( 18Ne, 6He). We study the optimal choices for the baseline, boost factor, and luminosity. We take a 50 kton iron calorimeter, a la ICAL@INO, as the far detector. We follow two complementary approaches for our study: (i) Fixing the number of useful ion decays and boost factor of the beam, and optimizing for the sensitivity reach between the two pairs of ions as a function of the baseline. (ii) Matching the shape of the spectrum between the two pairs of ions, and studying the requirements for baseline, boost factor, and luminosity. We find that for each pair of ions there are two baselines with very good sensitivity reaches: a short baseline with L [km]/γ 2.6 ( 8B+ 8Li) and L [km]/γ 0.8 ( 18Ne+ 6He), and a long "magic'' baseline. For γ ∼ 500, one would optimally use 18Ne and 6He at the short baseline for CP violation, 8B and 8Li at the magic baseline for the mass hierarchy, and either 18Ne and 6He at the short baseline or 8B and 8Li at the magic baseline for the sin 22θ 13 discovery.

Journal of High Energy Physics

Optimizing the greenfield Beta-beam

We show that the earth matter effects in the νe survival probability can be used to cleanly determine the third leptonic mixing angle θ13 and the sign of the atmospheric neutrino mass squared difference, Δm312, using a β-beam as a νe source. © 2007 The American Physical Society.

Physical Review D - Particles, Fields, Gravitation and Cosmology

Neutrino parameters from matter effects in the Î½e survival probability at long baselines

We show that a detector placed near a beta-beam storage ring can probe lepton number violating interactions, as predicted by supersymmetric theories with R-parity non-conservation. In the presence of such interactions, ντ can be produced during β-decay leading to tau leptons through weak interactions. Alternatively, electron neutrinos from β-decay of radioactive ions can produce tau leptons in a nearby detector through these interactions. The muons from the decay of these tau leptons can be readily identified in a small iron calorimeter detector and will signal violation of R-parity. © 2007 Elsevier B.V. All rights reserved.

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

Probing lepton number violating interactions with beta-beams

Long baseline oscillation experiments may well emerge as test beds for neutrino interactions as are present in R-parity violating supersymmetry. We show that flavour diagonal (FDNC) and flavour changing (FCNC) neutral currents arising therefrom prominently impact a neutrino β-beam experiment with the source at CERN and the detector at the proposed India-based Neutrino Observatory. These interactions may preclude any improvement of the present limit on θ13 and cloud the hierarchy determination unless the upper bounds on R{combining long solidus overlay} couplings, particularly λ′, become significantly tighter. If R{combining long solidus overlay} interactions are independently established then from the event rate a lower bound on θ13 may be set. We show that there is scope to see a clear signal of non-standard FCNC and FDNC interactions, particularly in the inverted hierarchy scenario and also sometimes for the normal hierarchy. In favourable cases, it may be possible to set lower and upper bounds on λ′ couplings. FCNC and FDNC interactions due to λ type R{combining long solidus overlay} couplings are unimportant. © 2006 Elsevier B.V. All rights reserved.

Can R-parity violating supersymmetry be seen in long baseline beta-beam experiments?

A high intensity source of a single neutrino flavour with known spectrum is most desirable for precision measurements, the consensus direction for the future. The beta beam is an especially suitable option for this. We discuss the prospects of a very long baseline beta beam experiment with a magnetized iron calorimeter detector. In particular, with the source at CERN and the detector at the proposed India-based Neutrino Observatory (INO) the baseline is near the 'magic' value where the effect of the CP phase is small. We observe that this experiment will be well suited to determine the sign of m32-m22 and will be capable of probing θ13 down to about 1°. © 2005 Elsevier B.V. all rights reserved.

Journal	Data powered by TypesetNuclear Physics B
Publisher	Data powered by TypesetELSEVIER SCIENCE BV
ISSN	0550-3213
Open Access	Yes