Publications (61)
A Consistent Picture Emerges: A Compact X-ray Continuum Emission Region in the Gravitationally Lensed Quasar SDSS J0924+0219
Chelsea L. MacLeod, Christopher Morgan, A. Mosquera +7
We analyze the optical, UV, and X-ray microlensing variability of the lensed quasar SDSS J0924+0219 using six epochs of Chandra data in two energy bands (spanning 0.4-8.0 keV, or 1…
Dirac-Brueckner-Hartree-Fock versus chiral effective field theory
F. Sammarruca, B. Chen, L. Coraggio +2
We compare nuclear and neutron matter predictions based on two different ab initio approaches to nuclear forces and the nuclear many-body problem. The first consists of a realistic…
Reddening and metallicity maps of the Milky Way bulge from VVV and 2MASS II. The complete high resolution extinction map and implications for Bulge studies
O. A. Gonzalez, M. Rejkuba, M. Zoccali +5
We use the Vista Variables in the Via Lactea (VVV) ESO public survey data to measure extinction values in the complete area of the Galactic bulge covered by the survey at high reso…
Direct Observation of Decoupled Structural and Electronic Transitions and an Ambient Pressure Monoclinic-Like Metallic Phase of VO
J. Laverock, S. Kittiwatanakul, A. A. Zakharov +5
We report the simultaneous measurement of the structural and electronic components of the metal-insulator transition of VO using electron and photoelectron spectroscopies and m…
The impact of charge symmetry and charge independence breaking on the properties of neutrons and protons in isospin-asymmetric nuclear matter
F. Sammarruca, L. White, B. Chen
We investigate the effects of charge independence and charge symmetry breaking in neutron-rich matter. We consider neutron and proton properties in isospin-asymmetric matter at nor…
C-axis Josephson Tunneling Between YBCO and Pb: Direct Evidence for Mixed Order Parameter Symmetry in a High-T_c Superconductor
K. A. Kouznetsov, A. G. Sun, B. Chen +10
We report a new class of -axis Josephson tunneling experiments in which a conventional superconductor (Pb) is deposited across a single twin boundary of a YBa_2Cu_3O_{7-δ} crys…
Steps for Solving the Transfer Equation for Arbitrary Flows in Stationary Spacetimes
B. Chen, R. Kantowski, E. Baron +2
We derive the radiative transfer equation for arbitrary stationary relativistic flows in stationary spacetimes, i.e. for steady-state transfer problems. We show how the standard ch…
XMM-Newton (cross)-calibration
M. G. F. Kirsch, B. Altieri, B. Chen +7
ESA's large X-ray space observatory XMM-Newton is in its fifth year of operations. We give a general overview of the status of calibration of the five X-ray instruments and the Opt…
Correlation between non-Fermi-liquid behavior and superconductivity in (Ca, La)(Fe,Co)As2 iron arsenides: A high-pressure study
W. Zhou, F. Ke, Xiaofeng Xu +11
Non-Fermi-liquid (NFL) phenomena associated with correlation effects have been widely observed in the phase diagrams of unconventional superconducting families. Exploration of the…
A Theoretical Investigation of Relativistic Spintronics
Z. Y. Wang, C. D. Xiong, B. Chen
Spintronics directly based on relativistic quantum mechanics is called as relativistic spintronics, which involves the study of active control and manipulation of 4D spin-tensor de…
Constraining the structure and formation of the Galactic bulge from a field in its outskirts. FLAMES-GIRAFFE spectra of about 400 red giants around (l,b)=(0°,-10°)
Stefan Uttenthaler, Mathias Schultheis, David. M. Nataf +3
The presence of two stellar populations in the Milky Way bulge has been reported recently. We aim at studying the abundances and kinematics of stars in the outer bulge, thereby pro…
Worldsheet and Spacetime Properties of p-p' System with B Field and Noncommutative Geometry
B. Chen, H. Itoyama, T. Matsuo +1
We study worldsheet and spacetime properties of the p-p' (p < p') open string system with constant B_{ij} field viewed from the Dp' brane. The description of this system in terms o…
Electronic structure of the kagome staircase compounds Ni3V2O8 and Co3V2O8
J. Laverock, B. Chen, A. R. H. Preston +5
The electronic structure of the kagome staircase compounds, Ni3V2O8 and Co3V2O8, has been investigated using soft x-ray absorption, soft x-ray emission, and resonant inelastic x-ra…
Time in Quantum Mechanics and Quantum Field Theory
Z. Y. Wang, B. Chen
W. Pauli pointed out that the existence of a self-adjoint time operator is incompatible with the semibounded character of the Hamiltonian spectrum. As a result, people have been ar…
Silicon microneedles array with biodegradable tips for transdermal drug delivery
B. Chen, J. Wei, Francis Tay +2
This paper presents the fabrication process, characterization results and basic functionality of silicon microneedles array with biodegradable tips. In order to avoid the main prob…
Including Absorption in Gordon's Optical Metric
B. Chen, R. Kantowski
We show that Gordon's optical metric on a curved spacetime can be generalized to include absorption by allowing the metric to become complex. We demonstrate its use in the realm of…
Study of Robust Sparsity-Aware RLS algorithms with Jointly-Optimized Parameters for Impulsive Noise Environments
Y. Yu, L. Lu, Y. Zakharov +2
This paper proposes a unified sparsity-aware robust recursive least-squares RLS (S-RRLS) algorithm for the identification of sparse systems under impulsive noise. The proposed algo…
Exploratory Chandra Observations of the Three Highest Redshift Quasars Known
W. N. Brandt, D. P. Schneider, X. Fan +13
We report on exploratory Chandra observations of the three highest redshift quasars known (z = 5.82, 5.99, and 6.28), all found in the Sloan Digital Sky Survey. These data, combine…
Upward curvature of the upper critical field and the V-shaped pressure dependence of in the noncentrosymmetric superconductor PbTaSe
J. R. Wang, Xiaofeng Xu, N. Zhou +10
The temperature evolution of the upper critical field in the noncentrosymmetric superconductor PbTaSe was determined via resistivity measurements down to 0.5 K. A p…
Strain dependence of bonding and hybridization across the metal-insulator transition of VO2
J. Laverock, L. F. J. Piper, A. R. H. Preston +8
Soft x-ray spectroscopy is used to investigate the strain dependence of the metal-insulator transition of VO2. Changes in the strength of the V 3d - O 2p hybridization are observed…
Resonant soft x-ray emission as a bulk probe of correlated electron behavior in metallic SrCaVO
J. Laverock, B. Chen, K. E. Smith +8
The evolution of electron correlation in SrCaVO has been studied using a combination of bulk-sensitive resonant soft x-ray emission spectroscopy (RXES), surface-s…
Gravitational Lensing Size Scales for Quasars
G. Chartas, C. Rhea, C. Kochanek +6
We review results from our monitoring observations of several lensed quasars performed in the optical, UV, and X-ray bands. Modeling of the multi-wavelength light curves provides c…
Drifting Pulsation Structure at the Very Beginning of the 2017 September 10 Limb Flare
M. Karlicky, B. Chen, D. E. Gary +2
Drifting pulsation structures (DPSs) are important radio fine structures usually observed at the beginning of eruptive solar flares. It has been suggested that DPSs carry important…
Electronic Nematicity Revealed by Torque Magnetometry in Iron Arsenide EuFe(AsP)
Xiaofeng Xu, W. H. Jiao, N. Zhou +6
Electronic nematics, an electron orientational order which breaks the underlying rotational symmetry, have been observed in iron pnictide superconductors several years after their…
Comparative Study of Quarkonium Transport in Hot QCD Matter
A. Andronic, P. B. Gossiaux, P. Petreczky +19
This document summarizes the efforts of the EMMI Rapid Reaction Task Force on "Suppression and (re)generation of quarkonium in heavy-ion collisions at the LHC", centered around the…
Greenland Telescope (GLT) Project: "A Direct Confirmation of Black Hole with Submillimeter VLBI"
M. Nakamura, J. -C. Algaba, K. Asada +20
The GLT project is deploying a new submillimeter (submm) VLBI station in Greenland. Our primary scientific goal is to image a shadow of the supermassive black hole (SMBH) of six bi…
Equivalence of the Fermat potential and the lensing potential approaches to computing the integrated Sachs-Wolfe effect
R. Kantowski, B. Chen, X. Dai
We show in detail that the recently derived expression for evaluating the integrated Sachs-Wolfe (ISW) temperature shift in the cosmic microwave background (CMB) caused by individu…
Quantum state transmission via a spin ladder as a robust data bus
Y. Li, T. Shi, B. Chen +2
We explore the physical mechanism to coherently transfer the quantum information of spin by connecting two spins to an isotropic antiferromagnetic spin ladder system as data bus. D…
Cosmology With A Dark Refraction Index
B. Chen, R. Kantowski
We review Gordon's optical metric and the transport equations for the amplitude and polarization of a geometrical optics wave traveling in a gravity field. We apply the theory to t…
Identification of A-colored Stars and Structure in the Halo of the Milky Way from SDSS Commissioning Data
B. Yanny, H. J. Newberg, S. Kent +21
A sample of 4208 objects with magnitude 15 < g* < 22 and colors of main sequence A stars has been selected from 370 square degrees of Sloan Digital Sky Survey (SDSS) commissioning…
Investigation of the effectiveness of non-inductive `multi-harmonic' electron cyclotron current drive through modeling multi-pass absorptions in the EXL-50 spherical tokamak
D. Banerjee, S. D. Song, H. S. Xie +14
The effectiveness of multiple electron cyclotron resonance (ECR) harmonics has been thoroughly investigated in context of high current drive efficiency, generally observed in fully…
Microscopic in-medium nucleon-nucleon cross sections with improved Pauli blocking effects
B. Chen, F. Sammarruca, C. A. Bertulani
We present updated predictions of effective elastic nucleon-nucleon cross sections intended for use in nucleus-nucleus reactions. A novel characteristic of the present approach com…
The Structure of the X-ray and Optical Emitting Regions of the Lensed Quasar Q 2237+0305
A. M. Mosquera, C. S. Kochanek, B. Chen +3
We use gravitational microlensing to determine the size of the X-ray and optical emission regions of the quadruple lens system Q 2237+0305. The optical half-light radius, log(R_{1/…
Nonabelian Monopoles from Matrices: Seeds of the Spacetime Structure
B. Chen, H. Itoyama, H. Kihara
We study the expectation value of (the product) of the one-particle projector (s) in the reduced matrix model and matrix quantum mechanics in general. This quantity is given by the…
Observing the Sun with the Atacama Large Millimeter-submillimeter Array (ALMA): Fast-Scan Single-Dish Mapping
S. M. White, K. Iwai, N. M. Phillips +31
The Atacama Large Millimeter-submillimeter Array (ALMA) radio telescope has commenced science observations of the Sun starting in late 2016. Since the Sun is much larger than the f…
Observing the Sun with Atacama Large Millimeter/submillimeter Array (ALMA): High Resolution Interferometric Imaging
M. Shimojo, T. S. Bastian, A. S. Hales +25
Observations of the Sun at millimeter and submillimeter wavelengths offer a unique probe into the structure, dynamics, and heating of the chromosphere; the structure of sunspots; t…
Correspondence between Noncommutative Soliton and Open String/D-brane System via Gaussian Damping Factor
B. Chen, H. Itoyama, T. Matsuo +1
The gaussian damping factor (g.d.f.) and the new interaction vertex with the symplectic tensor are the characteristic properties of the N-point scalar-vector scattering amplitudes…
A New Very Cool White Dwarf Discovered by the Sloan Digital Sky Survey
H. C. Harris, B. M. S. Hansen, J. Liebert +33
Early data taken during commissioning of the SDSS have resulted in the discovery of a very cool white dwarf. It appears to have stronger collision induced absorption from molecular…
Intrinsic pinning of FeSeS single crystals probed by torque magnetometry
Nan Zhou, Yue Sun, Q. Hou +14
Intrinsic pinning is caused by natural pinning centers that occur because of the modulation of the order parameter or weak superconducting layers. Early work has shown that intrins…
Low-energy V t2g orbital excitations in NdVO3
J. Laverock, B. Chen, A. R. H. Preston +7
The electronic structure of NdVO3, YVO3 has been investigated as a function of sample temperature using resonant inelastic soft x-ray scattering at the V L3-edge. Most of the obser…
Observation of inhomogeneous domain nucleation in epitaxial Pb(Zr,Ti)O3 capacitors
D. J. Kim, J. Y. Jo, T. H. Kim +4
We investigated domain nucleation process in epitaxial Pb(Zr,Ti)O3 capacitors under a modified piezoresponse force microscope. We obtained domain evolution images during polarizati…
CMOS compatible high-performance nanolasing based on perovskite-SiN hybrid integration
Z. He, B. Chen, Y. Hua +8
Coherent light sources in silicon photonics are the long-sought holy grail because silicon-based materials have indirect bandgap. Traditional strategies for realizing such sources,…
Evidence for two energy gaps and Fermi liquid behavior in SrPtAs superconductor
Xiaofeng Xu, B. Chen, W. H. Jiao +10
We report a detailed calorimetric study on single crystals of the 5-transition metal pnictide SrPt2As2 with a superconducting critical temperature 5K. The peculiar f…
Nonabelian Berry Phase, Yang-Mills Instanton and USp(2k) Matrix Model
B. Chen, H. Itoyama, H. Kihara
The nonabelian Berry phase is computed in the T dualized quantum mechanics obtained from the USp(2k) matrix model. Integrating the fermions, we find that each of the spacetime poin…
Prototyping and Test of the "Canis" HTS Planar Coil Array for Stellarator Field Shaping
D. Nash, D. A. Gates, W. S. Walsh +30
Thea Energy, Inc. is currently developing the "Eos" planar coil stellarator, the Company's first integrated fusion system capable of forming optimized stellarator magnetic fields w…
Effect of Selenium doping on the superconductivity of NbPd(SSe)
C. Q. Niu, J. H. Yang, Y. K. Li +9
We study the isovalent substitution effect by partially introducing Se on S site in the newly discovered superconductor NbPdS (6 K) whose upper critical field is f…
The GALAH Survey: Data Release 4
S. Buder, J. Kos, E. X. Wang +36
The stars of the Milky Way carry the chemical history of our Galaxy in their atmospheres as they journey through its vast expanse. Like barcodes, we can extract the chemical finger…
Coherent shift of localized bound pair in Bose Hubbard model
L. Jin, B. Chen, Z. Song
Based on the exact results obtained by Bethe ansatz, we demonstrate the existence of stable bound pair (BP) wave packet in Bose Hubbard model with arbitrary on-site interaction U.…
Intrinsic minimum average variance estimation for sufficient dimension reduction with symmetric positive definite matrices and beyond
B. Chen, S. Dai, Z. Yu
In this paper, we target the problem of sufficient dimension reduction with symmetric positive definite matrices valued responses. We propose the intrinsic minimum average variance…
Enhanced electron correlations at the SrxCa1-xVO3 surface
J. Laverock, J. Kuyyalil, B. Chen +5
We report hard x-ray photoemission spectroscopy measurements of the electronic structure of the prototypical correlated oxide SrxCa1-xVO3. By comparing spectra recorded at differen…
Holographic description of Kerr-Bolt-AdS-dS Spacetimes
B. Chen, A. M. Ghezelbash, V. Kamali +1
We show that there exists a holographic 2D CFT description of a Kerr-Bolt-AdS-dS spacetime. We first consider the wave equation of a massless scalar field propagating in extremal K…
Time as a Dynamical Variable
Z. Y. Wang, B. Chen, C. D. Xiong
There are enough reasons for us to consider time as a dynamical variable or operator; but according to Pauli's argument the existence of a self-adjoint time operator is incompatibl…
Chang-Refsdal Microlensed Type Ia Supernova Light Curves
H. Bagherpour, B. Chen, R. Kantowski +2
A description of the light curves of microlensed Type Ia supernovae (SNe Ia) as extended and expanding sources is presented. We give examples of what microlensing by stellar-mass C…
LOTIS, Super-LOTIS, SDSS and Tautenburg Observations of GRB 010921
H. S. Park, G. G. Williams, D. H. Hartmann +36
We present multi-instrument optical observations of the High Energy Transient Explorer (HETE-2)/Interplanetary Network (IPN) error box of GRB 010921. This event was the first gamma…
Major Scientific Challenges and Opportunities in Understanding Magnetic Reconnection and Related Explosive Phenomena in Solar and Heliospheric Plasmas
H. Ji, J. Karpen, A. Alt +105
Magnetic reconnection underlies many explosive phenomena in the heliosphere and in laboratory plasmas. The new research capabilities in theory/simulations, observations, and labora…
Evidence of s-wave superconductivity in the noncentrosymmetric LaIr
B. Li, C. Q. Xu, W. Zhou +9
Superconductivity in noncentrosymmetric compounds has attracted sustained interest in the last decades. Here we present a detailed study on the transport, thermodynamic properties…
p-p' System with B-field, Branes at Angles and Noncommutative Geometry
B. Chen, H. Itoyama, T. Matsuo +1
We study the generic system in the presence of constant NS 2-form field. We derive properties concerning with the noncommutativity of D-brane worldvolume, the…
On the Harmonic approximation for large Josephson junction coupling charge qubits
T. Shi, B. Chen, Z. Song +1
We revisit the harmonic approximation (HA) for a large Josephson junction interacting with some charge qubits through the variational approach for the quantum dynamics of the junct…
The u'g'r'i'z' Standard Star Network
J. A. Smith, D. L. Tucker, S. Kent +19
We present the 158 standard stars that define the u'g'r'i'z' photometric system. These stars form the basis for the photometric calibration of the Sloan Digital Sky Survey (SDSS).…
Untangling the global coronal magnetic field with multiwavelength observations
S. E. Gibson, A. Malanushenko, G. de Toma +16
Magnetism defines the complex and dynamic solar corona. Coronal mass ejections (CMEs) are thought to be caused by stresses, twists, and tangles in coronal magnetic fields that buil…
Robust Multiple-Range Coherent Quantum State Transfer
B. Chen, Y. D. Peng, Y. Li +1
We propose a multiple-range quantum communication channel to realize coherent two-way quantum state transport with high fidelity. In our scheme, an information carrier (a qubit) an…