Solar neutrino physics with low-threshold dark matter detectors

Dark matter detectors will soon be sensitive to Solar neutrinos via two distinct channels: coherent neutrino-nucleus scattering and neutrino electron elastic scattering. We establish an analysis method for extracting Solar model properties and neutrino properties from these measurements, including the possible effects of sterile neutrinos which have been hinted at by some reactor experiments and cosmological measurements. Even including sterile neutrinos, through the coherent scattering channel a 1 ton-year exposure with a low-threshold Germanium detector could improve on the current measurement of the normalization of the $^8$B Solar neutrino flux down to 3% or less. Combining with the elastic scattering data will provide constraints on both the high and low energy survival probability, and will improve on the uncertainty on the active-to-sterile mixing angle by a factor of two. This sensitivity to active-to-sterile transitions is competitive and complementary to forthcoming dedicated short baseline sterile neutrino searches with nuclear decays.Comment: 12 pages, 4 figures, 3 table

Implication of neutrino backgrounds on the reach of next generation dark matter direct detection experiments

As direct dark matter experiments continue to increase in size, they will become sensitive to neutrinos from astrophysical sources. For experiments that do not have directional sensitivity, coherent neutrino scattering (CNS) from several sources represents an important background to understand, as it can almost perfectly mimic an authentic WIMP signal. Here we explore in detail the effect of neutrino backgrounds on the discovery potential of WIMPs over the entire mass range of 500 MeV to 10 TeV. We show that, given the theoretical and measured uncertainties on the neutrino backgrounds, direct detection experiments lose sensitivity to light (~10 GeV) and heavy (~100 GeV) WIMPs with a spin-independent cross section below 10^{-45} cm^2 and 10^{-49} cm^2, respectively.Comment: 15 pages, 12 figures, 7Be fluxes revised, conclusions unchange

Supersymmetric Kaluza-Klein reductions of M-waves and MKK-monopoles

We investigate the Kaluza-Klein reductions to ten dimensions of the purely gravitational half-BPS M-theory backgrounds: the M-wave and the Kaluza-Klein monopole. We determine the moduli space of smooth (supersymmetric) Kaluza-Klein reductions by classifying the freely-acting spacelike Killing vectors which preserve some Killing spinor. As a consequence we find a wealth of new supersymmetric IIA configurations involving composite and/or bound-state configurations of waves, D0 and D6-branes, Kaluza-Klein monopoles in type IIA and flux/nullbranes, and some other new configurations. Some new features raised by the geometry of the Taub-NUT space are discussed, namely the existence of reductions with no continuous moduli. We also propose an interpretation of the flux 5-brane in terms of the local description (close to the branes) of a bound state of D6-branes and ten-dimensional Kaluza-Klein monopoles.Comment: 36 pages (v2: Reference added, "draft" mode disabled; v3: two singular reductions discarded, appendix on spin structures added, references updated

Complementarity of dark matter detectors in light of the neutrino background

Direct detection dark matter experiments looking for WIMP-nucleus elastic scattering will soon be sensitive to an irreducible background from neutrinos which will drastically affect their discovery potential. Here we explore how the neutrino background will affect future ton-scale experiments considering both spin-dependent and spin-independent interactions. We show that combining data from experiments using different targets can improve the dark matter discovery potential due to target complementarity. We find that in the context of spin-dependent interactions, combining results from several targets can greatly enhance the subtraction of the neutrino background for WIMP masses below 10 GeV/c$^2$ and therefore probe dark matter models to lower cross-sections. In the context of target complementarity, we also explore how one can tune the relative exposures of different target materials to optimize the WIMP discovery potential.Comment: 13 pages, 12 figures, 3 table

Groups and the Entropy Floor- XMM-Newton Observations of Two Groups

Using XMM-Newton spatially resolved X-ray imaging spectroscopy we obtain the temperature, density, entropy, gas mass, and total mass profiles for two groups of galaxies out to ~0.3 Rvir (Rvir, the virial radius). Our density profiles agree well with those derived previously, and the temperature data are broadly consistent with previous results but are considerably more precise. Both of these groups are at the mass scale of 2x10^13 Msolar but have rather different properties. They have considerably lower gas mass fractions at r<0.3 Rvir than the rich clusters. NGC2563, one of the least luminous groups for its X-ray temperature, has a very low gas mass fraction of ~0.004 inside 0.1 Rvir, which rises with radius. NGC4325, one of the most luminous groups at the same average temperature, has a higher gas mass fraction of 0.02. The entropy profiles and the absolute values of the entropy as a function of virial radius also differ, with NGC4325 having a value of ~100 keV cm-2 and NGC2563 a value of ~300 keV cm-2 at r~0.1 Rvir. For both groups the profiles rise monotonically with radius and there is no sign of an entropy "floor". These results are inconsistent with pre-heating scenarios which have been developed to explain the entropy floor in groups but are broadly consistent with models of structure formation which include the effects of heating and/or the cooling of the gas. The total entropy in these systems provides a strong constraint on all models of galaxy and group formation, and on the poorly defined feedback process which controls the transformation of gas into stars and thus the formation of structure in the universe.Comment: 22 pages, 2 figure

The geometry of null rotation identifications

The geometry of flat spacetime modded out by a null rotation (boost+rotation) is analysed. When embedding this quotient spacetime in String/M-theory, it still preserves one half of the original supersymmetries. Its connection with the BTZ black hole, supersymmetric dilatonic waves and one possible resolution of its singularity in terms of nullbranes are also discussed.Comment: 1+18 pages, 5 figures. v2 references adde

An Intensive Pedestrian Archaeological Survey of the Salado Creek Greenway, Wetmore Avenue to Eisenhauer Road, San Antonio, Bexar County, Texas Phase II: N. E. Loop 410 to Wetmore Avenue

The Center for Archaeological Research (CAR) of The University of Texas at San Antonio conducted an intensive pedestrian archaeological survey of the Salado Creek Greenway project located in San Antonio, Bexar County, Texas to fulfill contract requirements with Adams Environmental, Inc. of San Antonio. The survey was conducted under the requirements of the City of San Antonio Unified Development Code Chapter 35, Section 106 of the National Historic Preservation Act (NHPA) of 1966, and the Texas Antiquities Code. The survey was performed under Texas Antiquities Permit No. 4561, with Dr. Raymond Mauldin, CAR Assistant Director, serving as Principal Investigator and Antonia L. Figueroa serving as the Project Archaeologist. The work was conducted in advance of construction of a multi-use greenway trail proposed by the Parks and Recreation Department of the City of San Antonio. The project consists of development of a multi-use greenway trail running from Wetmore Avenue to Eisenhauer Road along the Salado Creek channel. The project area was surveyed in two phases with the first phase from N.E. Loop 410 to Eisenhauer Road completed in August 2007 (Munoz 2008) and the second phase from N.E. Loop 410 to Wetmore Avenue completed in February 2008. This report summarizes the results of the fieldwork from Phase II and provides recommendations regarding the management of cultural resources located on the project area. The archaeological investigations conducted by CAR resulted in the identification and recording of three new sites (41BX1764, 41BX1765 and 41BX1766).A portion of site 41BX841 was revisited as part of the pedestrian survey. However, the proposed trail alignment will not impact the site. The CAR recommends that sites 41BX1765 and 41BX1766 are not eligible for nomination to the National Register of Historical Places (NRHP). Shovel testing at 41BX1764 suggests the site is potentially eligible for the NRHP under criterion D. Because the site is located on the proposed trail alignment, the CAR recommends eligibility testing of the 41BX1764. All materials recovered during the investigations and all project related documents are curated at the Center for Archaeological Research

National Register of Historic Places Eligibility Testing of 41BX1764 (The Dos Mujeres Site), Bexar County, Texas

The Center for Archaeological Research (CAR) of The University of Texas at San Antonio conducted National Register of Historic Places (NRHP) eligibility testing at site 41BX1764. The archaeological testing associated with the Salado Creek Greenway project located in San Antonio, Bexar County, Texas was completed to fulfill contract requirements with Adams Environmental, Inc. of San Antonio. The survey was conducted under the requirements of the City of San Antonio Unified Development Code Chapter 35, Section 106 of the National Historic Preservation Act (NHPA) of 1966, and the Texas Antiquities Code. The archaeological testing was performed under Texas Antiquities Permit No. 4989, with Cynthia M. Muñoz, serving as Principal Investigator and Antonia L. Figueroa serving as Project Archaeologist. The work was conducted in advance of construction of a multi-use greenway trail proposed by the Parks and Recreation Department of the City of San Antonio. Results from testing revealed a multi-component site with a Late Prehistoric Toyah component. A deeper second component, of unknown date, was also identified. The Late Prehistoric component has been impacted by erosion and the existing trail, while the lower component appears to be in a secondary depositional context. No features were revealed during testing and the CAR does not recommend the site as eligible for the National Register of Historic Places (NRHP) or for formal designation as a State Archeological Landmark. All materials recovered during the investigation and all project related documents are curated at the Center for Archaeological Research