Prospects For Identifying Dark Matter With CoGeNT

It has previously been shown that the excess of events reported by the CoGeNT collaboration could be generated by elastically scattering dark matter particles with a mass of approximately 5-15 GeV. This mass range is very similar to that required to generate the annual modulation observed by DAMA/LIBRA and the gamma rays from the region surrounding the Galactic Center identified within the data of the Fermi Gamma Ray Space Telescope. To confidently conclude that CoGeNT's excess is the result of dark matter, however, further data will likely be needed. In this paper, we make projections for the first full year of CoGeNT data, and for its planned upgrade. Not only will this body of data more accurately constrain the spectrum of nuclear recoil events, and corresponding dark matter parameter space, but will also make it possible to identify seasonal variations in the rate. In particular, if the CoGeNT excess is the product of dark matter, then one year of CoGeNT data will likely reveal an annual modulation with a significance of 2-3$\sigma$. The planned CoGeNT upgrade will not only detect such an annual modulation with high significance, but will be capable of measuring the energy spectrum of the modulation amplitude. These measurements will be essential to irrefutably confirming a dark matter origin of these events.Comment: 6 pages, 6 figure

Fundamental Properties of the Highly Ionized Plasmas in the Milky Way

The cooling transition temperature gas in the interstellar medium (ISM), traced by the high ions, Si IV, C IV, N V, and O VI, helps to constrain the flow of energy from the hot ISM with T >10^6 K to the warm ISM with T< 2x10^4 K. We investigate the properties of this gas along the lines of sight to 38 stars in the Milky Way disk using 1.5-2.7 km/s resolution spectra of Si IV, C IV, and N V absorption from the Space Telescope Imaging Spectrograph (STIS), and 15 km/s resolution spectra of O VI absorption from the Far Ultraviolet Spectroscopic Explorer (FUSE). The absorption by Si IV and C IV exhibits broad and narrow components while only broad components are seen in N V and O VI. The narrow components imply gas with T<7x10^4 K and trace two distinct types of gas. The strong, saturated, and narrow Si IV and C IV components trace the gas associated with the vicinities of O-type stars and their supershells. The weaker narrow Si IV and C IV components trace gas in the general ISM that is photoionized by the EUV radiation from cooling hot gas or has radiatively cooled in a non-equilibrium manner from the transition temperature phase, but rarely the warm ionized medium (WIM) probed by Al III. The broad Si IV, C IV, N V, and O VI components trace collisionally ionized gas that is very likely undergoing a cooling transition from the hot ISM to the warm ISM. The cooling process possibly provides the regulation mechanism that produces N(C IV)/N(Si IV) = 3.9 +/- 1.9. The cooling process also produces absorption lines where the median and mean values of the line widths increase with the energy required to create the ion.Comment: Accepted for publication in the ApJ. Only this PDF file contains all the figures and tables in a single fil

Vertex operators and the geometry of moduli spaces of framed torsion-free sheaves

We define complexes of vector bundles on products of moduli spaces of framed rank r torsion-free sheaves on the complex projective plane. The top non-vanishing Chern classes of the cohomology of these complexes yield actions of the r-colored Heisenberg and Clifford algebras on the equivariant cohomology of the moduli spaces. In this way we obtain a geometric realization of the boson-fermion correspondence and related vertex operators.Comment: 36 pages; v2: Definition of geometric Heisenberg operators modified; v3: Minor typos correcte

Quantum-field dynamics of expanding and contracting Bose-Einstein condensates

We analyze the dynamics of quantum statistics in a harmonically trapped Bose-Einstein condensate, whose two-body interaction strength is controlled via a Feshbach resonance. From an initially non-interacting coherent state, the quantum field undergoes Kerr squeezing, which can be qualitatively described with a single mode model. To render the effect experimentally accessible, we propose a homodyne scheme, based on two hyperfine components, which converts the quadrature squeezing into number squeezing. The scheme is numerically demonstrated using a two-component Hartree-Fock-Bogoliubov formalism.Comment: 9 pages, 4 figure

Quartet S Wave Neutron Deuteron Scattering in Effective Field Theory

The real and imaginary part of the quartet S wave phase shift in nd scattering (^4 S_{3/2}) for centre-of-mass momenta of up to 300 MeV (E_cm \approx 70 MeV) is presented in effective field theory, using both perturbative pions and a theory in which pions are integrated out. As available, the calculation agrees with both experimental data and potential model calculations, but extends to a higher, so far untested momentum r\'egime above the deuteron breakup point. A Lagrangean more feasible for numerical computations is derived.Comment: 27 pages LaTeX2e with 11 figures, uses packages includegraphicx (6 .eps files), color and feynmp (necessary Metapost files included). Corrections in bibliography and NNLO results added above breaku

Quantum measurement and decoherence

Distribution functions defined in accord with the quantum theory of measurement are combined with results obtained from the quantum Langevin equation to discuss decoherence in quantum Brownian motion. Closed form expressions for wave packet spreading and the attenuation of coherence of a pair of wave packets are obtained. The results are exact within the context of linear passive dissipation. It is shown that, contrary to widely accepted current belief, decoherence can occur at high temperature in the absence of dissipation. Expressions for the decoherence time with and without dissipation are obtained that differ from those appearing in earlier discussions

Abortion provision in Northern Ireland: the views of health professionals working in obstetrics and gynaecology units

Introduction: Abortion became decriminalised in Northern Ireland in October 2019. Until that point there existed no evidence concerning the views of health professionals on decriminalisation or on their willingness to be involved in abortion care. The purpose of this study was to address this lack of evidence, including all categories of health professionals working in obstetrics and gynaecology units in Northern Ireland. Methods: The online survey was targeted at medical, nursing and midwifery staff working in the obstetrics and gynaecology units in each Health and Social Care (HSC) Trust in Northern Ireland. The survey was issued via clinical directors in each Trust using the REDCap platform. Results: The findings showed widespread support for decriminalisation of abortion up until 24 weeks’ gestation (n=169, 54%). The majority of clinicians stated they were willing to provide abortions in certain circumstances (which were undefined) (n=188, 60% medical abortions; n=157, 50% surgical abortions). Despite regional variation, the results show that there are sufficient numbers of clinicians to provide a service within each HSC Trust. The results indicate that many clinicians who report a religious affiliation are also supportive of decriminalisation (n=46, 51% Catholic; n=53, 45% Protestant) and are willing to provide care, countering the assumption that those of faith would all raise conscientious objections to service provision. Conclusions: The findings of this study are very encouraging for the development, implementation and delivery of local abortion care within HSC Trusts in Northern Ireland and should be of value in informing commissioners and providers about the design of a service model and its underpinning training programmes

Discovery of the first tau Sco analogues: HD 66665 and HD 63425

The B0.2 V magnetic star tau Sco stands out from the larger population of massive OB stars due to its high X-ray activity, peculiar wind diagnostics and highly complex magnetic field. This paper presents the discovery of the first two tau Sco analogues - HD 66665 and HD 63425, identified by the striking similarity of their UV spectra to that of tau Sco. ESPaDOnS spectropolarimetric observations were secured by the Magnetism in Massive Stars CFHT Large Program, in order to characterize the stellar and magnetic properties of these stars. CMFGEN modelling of optical ESPaDOnS spectra and archived IUE UV spectra showed that these stars have stellar parameters similar to those of tau Sco. A magnetic field of similar surface strength is found on both stars, reinforcing the connection between the presence of a magnetic field and wind peculiarities. However, additional phase-resolved observations will be required in order to assess the potential complexity of the magnetic fields, and verify if the wind anomalies are linked to this property.Comment: 6 pages, 2 tables, 3 figures. Accepted for publication in MNRAS. The definitive version will be available at www.blackwel-synergy.co

Understanding the dynamics of segregation bands of simulated granular material in a rotating drum

Axial segregation of a binary mixture of grains in a rotating drum is studied using Molecular Dynamics (MD) simulations. A force scheme leading to a constant restitution coefficient is used and shows that axial segregation is possible between two species of grains made of identical material differing by size. Oscillatory motion of bands is investigated and the influence of the frictional properties elucidated. The mechanism of bands merging is explained using direct imaging of individual grains