Measuring the muon's anomalous magnetic moment to 0.14 ppm

The anomalous magnetic moment (g-2) of the muon was measured with a precision of 0.54 ppm in Experiment 821 at Brookhaven National Laboratory. A difference of 3.2 standard deviations between this experimental value and the prediction of the Standard Model has persisted since 2004; in spite of considerable experimental and theoretical effort, there is no consistent explanation for this difference. This comparison hints at physics beyond the Standard Model, but it also imposes strong constraints on those possibilities, which include supersymmetry and extra dimensions. The collaboration is preparing to relocate the experiment to Fermilab to continue towards a proposed precision of 0.14 ppm. This will require 20 times more recorded decays than in the previous measurement, with corresponding improvements in the systematic uncertainties. We describe the theoretical developments and the experimental upgrades that provide a compelling motivation for the new measurement.Comment: 5 pages, 1 figure, presented at International Nuclear Physics Conference 2010 (INPC 2010

Solar Carbon Monoxide, Thermal Profiling, and the Abundances of C, O, and their Isotopes

A solar photospheric "thermal profiling" analysis is presented, exploiting the infrared rovibrational bands of carbon monoxide (CO) as observed with the McMath-Pierce Fourier transform spectrometer (FTS) at Kitt Peak, and from above the Earth's atmosphere by the Shuttle-borne ATMOS experiment. Visible continuum intensities and center-limb behavior constrained the temperature profile of the deep photosphere, while CO center-limb behavior defined the thermal structure at higher altitudes. The oxygen abundance was self consistently determined from weak CO absorptions. Our analysis was meant to complement recent studies based on 3-D convection models which, among other things, have revised the historical solar oxygen (and carbon) abundance downward by a factor of nearly two; although in fact our conclusions do not support such a revision. Based on various considerations, an oxygen abundance of 700+/-100 ppm (parts per million relative to hydrogen) is recommended; the large uncertainty reflects the model sensitivity of CO. New solar isotopic ratios also are reported for 13C, 17O, and 18O.Comment: 90 pages, 19 figures (some with parts "a", "b", etc.); to be published in the Astrophysical Journal Supplement

The Mg 2 h and k lines in a sample of dMe and dM stars

Both Mg II h and k line fluxes are presented for a sample of 4 dMe and 3 dM stars obtained with the IUE satellite in the long wavelength, low dispersion mode. The observed fluxes are converted to stellar surface flux units and the importance of chromospheric non radiative heating in this sample of M dwarf stars is intercompared. In addition, the net chromospheric radiative losses due to the Ca II H and K lines in those stars in the sample for which calibrated Ca II H and K line data exist are compared. Active region filling factors which likely give rise to the observed optical and ultraviolet chromospheric emission are estimated. The implications of the results for homogeneous, single component stellar model chromospheres analyses are discussed

Relationship between X-ray and ultraviolet emission of flares from dMe stars observed by XMM-Newton

We present simultaneous ultraviolet and X-ray observations of the dMe-type flaring stars AT Mic, AU Mic, EV Lac, UV Cet and YZ CMi obtained with the XMM-Newton observatory. During 40 hours of simultaneous observation we identify 13 flares which occurred in both wave bands. For the first time, a correlation between X-ray and ultraviolet flux for stellar flares has been observed. We find power-law relationships between these two wavelength bands for the flare luminosity increase, as well as for flare energies, with power-law exponents between 1 and 2. We also observe a correlation between the ultraviolet flare energy and the X-ray luminosity increase, which is in agreement with the Neupert effect and demonstrates that chromospheric evaporation is taking place.Comment: 8 pages, 4 figures, 3 tables, accepted by A&A (30 Sept. 2004

Recent atmospheric neutrino results from Soudan 2

An updated measurement of the atmospheric nu_mu/nu_e ratio-of-ratios, 0.68+-0.11+-0.06, has been obtained using a 4.6-kty exposure of the Soudan-2 iron tracking calorimeter. The L/E distributions have been analyzed for effects of nu_mu -> nu_x oscillations, and an allowed region in the Delta m^2 vs. sin^2 2 theta plane has been determined.Comment: 3 pages, 4 figures; presented at TAUP99, the 6th Int. Workshop on Topics in Astroparticle and Underground Physics, Sept. 6-10, 1999, College de France, Paris, Franc

Reversal-free CaIIH profiles: a challenge for solar chromosphere modeling in quiet inter-network

We study chromospheric emission to understand the temperature stratification in the solar chromosphere. We observed the intensity profile of the CaIIH line in a quiet Sun region close to the disk center at the German Vacuum Tower Telescope. We analyze over 10^5 line profiles from inter-network regions. For comparison with the observed profiles, we synthesize spectra for a variety of model atmospheres with a non local thermodynamic equilibrium (NLTE) radiative transfer code. A fraction of about 25% of the observed CaIIH line profiles do not show a measurable emission peak in H_{2v} and H_{2r} wavelength bands (reversal-free). All of the chosen model atmospheres with a temperature rise fail to reproduce such profiles. On the other hand, the synthetic calcium profile of a model atmosphere that has a monotonic decline of the temperature with height shows a reversal-free profile that has much lower intensities than any observed line profile. The observed reversal-free profiles indicate the existence of cool patches in the interior of chromospheric network cells, at least for short time intervals. Our finding is not only in conflict with a full-time hot chromosphere, but also with a very cool chromosphere as found in some dynamic simulations.Comment: 8 pages, accepted in A&

Surface patterning of polyacrylamide gel using scanning electrochemical cell microscopy (SECCM)

Scanning electrochemical cell microscopy is introduced as a new tool for the synthesis and deposition of polymers on SAM-functionalised Au surfaces. The deposition of poly(N-hydroxyethyl acrylamide) is shown to be enhanced through the electrochemical generation of activating Cu(I)Cl/Me6TREN catalyst. Initiation of the polymerisation reaction is most likely due to in situ generation of reactive oxygen species following oxygen reduction