Publications (64)
Direct observation of nanometer-scale pinning sites in (Nd,Eu,Gd)BaCuO single crystals
P. Das, M. R. Koblischka, S. Turner +4
We report on the observation of self-organized stripe-like structures on the as-grown surface and in the bulk of (Nd,Eu,Gd)BaCuO single crystals. The periodicity of the…
Small-angle neutron scattering study of the vortex lattice in superconducting LuNi2B2C
J. M. Densmore, P. Das, K. Rovira +8
We present studies of the magnetic field distribution around the vortices in LuNi2B2C. Small-angle neutron scattering measurements of the vortex lattice (VL) in this material were…
Excitation of a bosonic mode by electron tunneling into a cuprate superconductor
P. Das, M. R. Koblischka, H. Rosner +2
We performed scanning tunneling spectroscopic experiments on hole-doped NdBaCuO. The d/d curves obtained at 4.2 K are asymmetric with clear peak-dip and hump…
Measurement of -decay end point energy with Planar HPGe detector
T. Bhattacharjee, Deepak Pandit, S. K. Das +7
The end point energies of nuclear decays have been measured with a segmented planar Ge LEPS detector using both singles and coincidence techniques. The coincidence ha…
Neutron-Antineutron Oscillations: Theoretical Status and Experimental Prospects
D. G. Phillips, W. M. Snow, K. Babu +60
This paper summarizes the relevant theoretical developments, outlines some ideas to improve experimental searches for free neutron-antineutron oscillations, and suggests avenues fo…
The PN.S Elliptical Galaxy Survey: a standard LCDM halo around NGC 4374?
N. R. Napolitano, A. J. Romanowsky, M. Capaccioli +10
As part of our current programme to test LCDM predictions for dark matter (DM) haloes using extended kinematical observations of early-type galaxies, we present a dynamical analysi…
Exploring the fragile antiferromagnetic superconducting phase in CeCoIn5
E. Blackburn, P. Das, M. R. Eskildsen +5
CeCoIn5 is a heavy fermion Type-II superconductor which exhibits clear indications of Pauli-limited superconductivity. A variety of measurements give evidence for a transition at h…
Dominance of Electron-Magnon Scattering in Itinerant Ferromagnet Fe3GeTe2
P. Saha, M. Singh, V. Nagpal +2
Fe3GeTe2 is a 2-dimensional van der Waals material exhibiting itinerant ferromagnetism upto 230 K. Here, we study aspects of scattering mechanism in Fe3Ge2Te2 single crystals via r…
An Orbital Solution for WASP-12 b: Updated Ephemeris and Evidence for Decay Leveraging Citizen Science Data
Avinash S. Nediyedath, Martin J. Fowler, A. Norris +11
NASA Citizen Scientists have used Exoplanet Transit Interpretation Code (EXOTIC) to reduce 40 sets of time-series images of WASP-12 taken by privately owned telescopes and a 6-inch…
Observations of Pauli Paramagnetic Effects on the Flux Line Lattice in CeCoIn5
J. S. White, P. Das, M. R. Eskildsen +12
From small-angle neutron scattering studies of the flux line lattice (FLL) in CeCoIn5, with magnetic field applied parallel to the crystal c-axis, we obtain the field- and temperat…
Dimensional Crossover of Mass Anisotropy in Ta-doped WTe2
P. Das, D. Das, P. Kumar +2
The observation of extremely large magnetoresistance in WTe2 has attracted considerable attention towards understanding its underlying origin. With its layered van der Waals struct…
Strong cooperative coupling of pressure-induced magnetic order and nematicity in FeSe
K. Kothapalli, A. E. Böhmer, W. T. Jayasekara +10
A hallmark of the iron-based superconductors is the strong coupling between magnetic, structural and electronic degrees of freedom. However, a universal picture of the normal state…
Multiferroicity in the Presence of Exchange Bias: The Case of Spinel CoMn2O4
P. Kumar, P. Das, B. K. Kuanr +1
Ferrimagnetic spinel materials of formula AB2X4, where A and B are transition metals and X is oxygen or sulphur, hold promise for the realization of multiferroic characteristics. I…
Field Dependence of the Superconducting Basal Plane Anisotropy of TmNi2B2C
P. Das, J. M. Densmore, C. Rastovski +7
The superconductor TmNi2B2C possesses a significant four-fold basal plane anisotropy, leading to a square Vortex Lattice (VL) at intermediate fields. However, unlike other members…
Intrinsic Variability of the Vela Pulsar: Lognormal Statistics and Theoretical Implications
Iver H. Cairns, S. Johnston, P. Das
Individual pulses from pulsars have intensity-phase profiles that differ widely from pulse to pulse, from the average profile, and from phase to phase within a pulse. Widely accept…
Probing the kinematics of early-type galaxy halos using planetary nebulae
L. Coccato, O. Gerhard, M. Arnaboldi +11
We present first results of a study of the halo kinematics for a sample of early type galaxies using planetary nebulae (PNe) as kinematical tracers. PNe allow to extend up to sever…
The PN.S Elliptical Galaxy Survey: the dark matter in NGC 4494
N. R. Napolitano, A. J. Romanowsky, L. Coccato +12
We present new Planetary Nebula Spectrograph observations of the ordinary elliptical galaxy NGC 4494, resulting in positions and velocities of 255 PNe out to 7 effective radii (25…
Higgs Physics at the HL-LHC and HE-LHC
M. Cepeda, S. Gori, P. Ilten +374
The discovery of the Higgs boson in 2012, by the ATLAS and CMS experiments, was a success achieved with only a percent of the entire dataset foreseen for the LHC. It opened a lands…
New signatures of phase transition from Statistical Models of Nuclear multifragmentation
G. Chaudhuri, S. Mallik, P. Das +1
The study of liquid-gas phase transition in heavy ion collisions has generated a lot of interest amongst the nuclear physicists in the recent years. In heavy ion collisions, there…
Role of p-induced population of medium mass(A 150) neutron rich nuclei
D. Banerjee, A. Saha, T. Bhattacharjee +11
Excitation functions were measured by stacked-foil activation technique for the Nd(p, xpyn) reaction using 97.65 enriched Nd target. Measurement up to 50$%…
Breaking Beta: A comparison of mass modelling methods for spherical systems
J. I. Read, G. A. Mamon, E. Vasiliev +6
We apply four different mass modelling methods to a suite of publicly available mock data for spherical stellar systems. We focus on the recovery of the density and velocity anisot…
First-order derivative of cluster size as a new signature of phase transition in heavy ion collisions at intermediate energies
P. Das, S. Mallik, G. Chaudhuri
The phenomenon of liquid-gas phase transition occurring in heavy ion collisions at intermediate energies is a subject of contemporary interest. Phase transition is usually characte…
PAC study of the static and dynamic aspects of metal atom inside C60 cage
S. K. Das, R. Guin, D. Banerjee +5
30 keV 111mCd and 50 keV 199mHg beams from ISOLDE were used to implant on preformed target of C60 with the thickness of 1 mg/cm2. Endofullerene compounds, viz.,111mCd@C60 and 199mH…
Intrinsic Variability and Field Statistics for the Vela Pulsar: 3. Two-Component Fits and Detailed Assessment of Stochastic Growth Theory
Iver H. Cairns, P. Das, P. A. Robinson +1
The variability of the Vela pulsar (PSR B0833-45) corresponds to well-defined field statistics that vary with pulsar phase, ranging from Gaussian intensity statistics off-pulse to…
Electronic phase separation due to magnetic polaron formation in the semimetallic ferromagnet EuB - A weakly-nonlinear-transport study
A. Amyan, P. Das, J. Müller +1
We report measurements of weakly nonlinear electronic transport, as measured by third-harmonic voltage generation , in the low-carrier density semimetallic ferromagnet EuB…
Effect of Spin Fluctuations on Magnetoresistance and Anomalous Hall Effect in the Chiral Magnet Co8Zn8Mn4
P. Saha, P. Das, M. Singh +2
The beta Mn type Co-Zn-Mn alloys have seized significant attention due to their ability to host skyrmions at room temperature. Here we analyse the unconventional magneto-transport…
Quantum Linear Magnetoresistance and Fermi Liquid Behavior in Kagome Metal Ni3In2S2
P. Das, P. Saha, M. Singh +2
Kagome metals gain attention as they manifest a spectrum of quantum phenomena, including superconductivity, charge order, frustrated magnetism, and intertwined correlated states of…
Certain observations on selection principles related to bornological covers using ideals
D. Chandra, P. Das, S. Das
We study selection principles related to bornological covers using the notion of ideals. We consider ideals and on and standard ideal orderings $KB,…
Large magnetocapacitance in electronic ferroelectric manganite systems
Ujjal Chowdhury, Sudipta Goswami, Dipten Bhattacharya +4
We have observed a sizable positive magnetocapacitance () in perovskite PrCaMnO and bilayer Pr(SrCa)MnO system under…
Identification of a long lived decaying isomer in Pm
A. Saha, T. Bhattacharjee, D. Banerjee +9
The decay of odd-odd Pm has been studied by populating the nucleus with the Nd(p,n)Pm reaction at E = 8.0 MeV using 97 enriched Nd targ…
Absence of a static in-plane magnetic moment in the "hidden-order" phase of URuSi
P. Das, R. E. Baumbach, E. D. Bauer +6
We have carried out a careful magnetic neutron scattering study of the heavy fermion compound \URuSi\ to probe the possible existence of a small magnetic moment parallel to tetrago…
Conferences with Internet Web-Casting as Binding Events in a Global Brain: Example Data From Complexity Digest
A. Das, G. Mayer-Kress, C. Gershenson +1
There is likeness of the Internet to human brains which has led to the metaphor of the world-wide computer network as a `Global Brain'. We consider conferences as 'binding events'…
Galactic Phylogenetics
P. Jofre, P. Das
Phylogenetics is a widely used concept in evolutionary biology. It is the reconstruction of evolutionary history by building trees that represent branching patterns and sequences.…
On the Experimental Evidence for Possible Superconductivity in LK99
H. Singh, A. Gautam, M. Singh +8
The desire to create an energy efficient world is bound to be incomplete without the discovery of a room temperature superconductor at ambient pressure. A recent report on the room…
Change of 7Be decay rate in exohedral and endohedral C60 fullerene compounds and its implications
A. Ray, P. Das, S. K. Saha +7
The half-life of 7Be implanted in a C60 pellet and gold foil has been measured to be about the same within about 0.2%. Using a radiochemical technique, we also measured that the pr…
Comparison of an approximately isothermal gravitational potentials of elliptical galaxies based on X-ray and optical data
E. Churazov, S. Tremaine, W. Forman +6
We analyze six X-ray bright elliptical galaxies, observed with Chandra and XMM-Newton, and approximate their gravitational potentials by isothermal spheres phi(r)=v_c^2 ln(r) over…
The GECKOS survey: Jeans anisotropic models of edge-on discs uncover the impact of dust and kinematic structures
T. H. Rutherford, A. Fraser-McKelvie, E. Emsellem +17
The central regions of disc galaxies host a rich variety of stellar structures: nuclear discs, bars, bulges, and boxy-peanut (BP) bulges. These components are often difficult to di…
Vortex lattice studies in CeCoIn5 with H perpendicular to c
P. Das, J. S. White, A. T. Holmes +10
We present small angle neutron scattering studies of the vortex lattice (VL) in CeCoIn5 with magnetic fields applied parallel (H) to the antinodal [100] and nodal [110] directions.…
Evidence of the Excited X(5)-like Critical-Point Symmetry Structures in 152Sm
S. Basak, S. Rajbanshi, T. Bhattacharjee +23
The positive-parity structure of 152Sm has been investigated through high-statistics γ-ray spectroscopy following the (150Nd(α,2n)152Sm reaction at Elab = 26 MeV. Several collect…
Dissipation of angular momentum in light heavy ion collision
C. Bhattacharya, S. Bhattacharya, T. Bhattacharjee +6
The inclusive energy distributions of fragments (4Z7) emitted in the reactions O (116 MeV) + Al, Si, Ne (145 MeV) + Al, Co hav…
Antiferromagnetic Stacking of Ferromagnetic Layers and Doping Controlled Phase Competition in CaSrCoAs
Bing Li, Y. Sizyuk, N. S. Sangeetha +9
In search of a quantum phase transition between the two-dimensional (D) ferromagnetism of CaCoAs and stripe-type antiferromagnetism in SrCoAs, we rathe…
Intrinsic Variability and Field Statistics for the Vela Pulsar: 2. Systematics and Single-Component Fits
Iver H. Cairns, S. Johnston, P. Das
Individual pulses from pulsars have intensity-phase profiles that differ widely from pulse to pulse, from the average profile, and from phase to phase within a pulse. Widely accept…
Planetary nebulae in the elliptical galaxy NGC 4649 (M 60): kinematics and distance redetermination
A. M. Teodorescu, R. H. Mendez, F. Bernardi +3
Using a slitless spectroscopy method with (a) the 8.2 m Subaru telescope and its FOCAS Cassegrain spectrograph, and (b) the ESO Very Large Telescope (VLT) unit 1 (Antu) and its FOR…
Multiplicity Derivative: A new signature of first order phase transition in intermediate energy heavy ion collision
S. Mallik, G. Chaudhuri, P. Das +1
Measurement of M, the total multiplicity, for central collision between comparable mass heavy ions can provide a signature for first order phase transition. The derivative of M wit…
Unravelling the origins of S0 galaxies using maximum likelihood analysis of planetary nebulae kinematics
A. Cortesi, M. R. Merrifield, M. Arnaboldi +12
To investigate the origins of S0 galaxies, we present a new method of analyzing their stellar kinematics from discrete tracers such as planetary nebulae. This method involves binni…
Magnetically-driven electronic phase separation in the semimetallic ferromagnet EuB
P. Das, A. Amyan, J. Brandenburrg +4
From measurements of fluctuation spectroscopy and weak nonlinear transport on the semimetallic ferromagnet EuB we find direct evidence for magnetically-driven electronic phase…
A New Evidence of Interplay Between Tetrahedral and Octahedral Symmetries and Symmetry Breaking: Exotic Rotational Bands in Sm
S. Basak, D. Kumar, T. Bhattacharjee +30
We report on an experimental evidence for a new, second tetrahedral band in Sm. It was populated via fusion evaporation reaction, $^{150}{\rm Nd}(α, 2n)…
Kinematic properties of early-type galaxy haloes using planetary nebulae
L. Coccato, O. Gerhard, M. Arnaboldi +11
We present new planetary nebulae (PNe) positions, radial velocities, and magnitudes for 6 early-type galaxies obtained with the Planetary Nebulae Spectrograph, their two-dimensiona…
Enhanced orbital electron-capture nuclear decay rate in compact medium
A. Ray, P. Das, S. K. Saha +2
The eigenstate energies of an atom increase under spatial confinement and this effect should also increase the electron density of the orbital electrons at the nucleus thus increas…
Magnetization hysteresis and time decay measurements in FeSeTe : Evidence for fluctuation in mean free path induced pinning
P. Das, Ajay D. Thakur, Anil K. Yadav +5
We present results of magnetic measurements relating to vortex phase diagram in a single crystal of FeSeTe which displays second magnetization peak anomaly for $H \…
Dissipative collisions in O + Al at E=116 MeV
C. Bhattacharya, K. Mullick, S. Bhattacharya +8
The inclusive energy distributions of fragments (3Z7) emitted in the reaction O + Al at 116 MeV have been measured in the angular range $θ_{l…
Studying stellar populations in Omega Centauri with phylogenetics
P. Jofré, C. Aguilera-Gómez, P. Villarreal +14
The nature and formation history of our Galaxy's largest and most enigmatic stellar cluster, known as Omega Centauri (ocen) remains debated. Here, we offer a novel approach to dise…
Controlled creation and annihilation of stringless robust emergent magnetic monopoles in artificial spin ice
N. Keswani, R. Lopes, Y. Nakajima +6
Magnetic analogue of an isolated free electric charge, i.e., a magnet with a single north or south pole, is a long sought-after particle which remains elusive so far. In magnetical…
Short-range magnetic correlations in quasicrystalline i-Tb-Cd
P. Das, A. Kreyssig, G. S. Tucker +11
We report on elastic and inelastic neutron scattering from single-grain isotopically-enriched samples to elucidate the local magnetic correlations between Tb moments in quas…
Self-hybridization within non-Hermitian plasmonic systems
H. Lourenço-Martins, P. Das, L. H. G. Tizei +2
Common intuition in physics is based on the concept of orthogonal eigenmodes. Those are well de- fined solutions of Hermitian equations used to describe many physical situations, f…
Neutron-Antineutron Oscillations: A Snowmass 2013 White Paper
K. Babu, S. Banerjee, D. V. Baxter +69
This paper summarizes discussions of the theoretical developments and the studies performed by the NNbarX collaboration for the 2013 Snowmass Community Summer Study.
Dark-Matter Content of Early-Type Galaxies with Planetary Nebulae
N. R. Napolitano, A. J. Romanowsky, L. Coccato +10
We examine the dark matter properties of nearby early-type galaxies using planetary nebulae (PNe) as mass probes. We have designed a specialised instrument, the Planetary Nebula Sp…
Low lying spectroscopy of odd-odd Eu
T. Bhattacharjee, D. Banerjee, S. K. Das +6
Electron Capture (EC) decay of Gd( = 48d) to the low lying states of Eu has been studied using high-resolution ray spectroscopy. The Gd a…
Metastable Vortex Lattice Phases in Superconducting MgB2
P. Das, C. Rastovski, T. R. O'Brien +6
The vortex lattice (VL) symmetry and orientation in clean type-II superconductors depends sensitively on the host material anisotropy, vortex density and temperature, frequently le…
Probing spin dynamics of 2D excitons with twisted light
A. K. Pattanayak, P. Das, D. Chakrabarty +5
We propose a mechanism of intravalley spin-flip scattering in spin-valley coupled two dimensional systems by transferring momentum of light into exciton center of mass using optica…
Magnetization reversal of dipolar coupled nanomagnets studied by two-dimensional electron gas based micro-Hall magnetometry
N. Keswani, Y. Nakajima, N. Chauhan +6
We report here the results of two-dimensional electron gas based micro-Hall magnetometry measurements and micromagnetic simulations of dipolar coupled nanomagnets of Ni80Fe20 arran…
Dependence of Energy Gap and Asymmetry of Coherence Peaks in NdBaCuO
P. Das, M. R. Koblischka, Th. Wolf +2
We report here the results of scanning tunneling spectroscopic experiments performed on hole doped NdBaCuO single crystals of values of 76 K, 93.5 K and 95.5…
Compelling experimental evidence of a Dirac cone in the electronic structure of a 2D Silicon layer
S. Sadeddine, H. Enriquez, A. Bendounan +7
The remarkable properties of graphene stem from its two-dimensional (2D) structure, with a linear dispersion of the electronic states at the corners of the Brillouin zone (BZ) form…
Effect of hyperons on phase coexistence in strange matter
P. Das, S. Mallik, G. Chaudhuri
The study of liquid gas phase transition in fragmentation of nuclei in heavy ion collisions has been extended to the strangeness sector using the statistical model for multifragmen…