Performance of Major Flare Watches from the Max Millennium Program (2001-2010)

The physical processes that trigger solar flares are not well understood and significant debate remains around processes governing particle acceleration, energy partition, and particle and energy transport. Observations at high resolution in energy, time, and space are required in multiple energy ranges over the whole course of many flares in order to build an understanding of these processes. Obtaining high-quality, co-temporal data from ground- and space- based instruments is crucial to achieving this goal and was the primary motivation for starting the Max Millennium program and Major Flare Watch (MFW) alerts, aimed at coordinating observations of all flares >X1 GOES X-ray classification (including those partially occulted by the limb). We present a review of the performance of MFWs from 1 February 2001 to 31 May 2010, inclusive, that finds: (1) 220 MFWs were issued in 3,407 days considered (6.5% duty cycle), with these occurring in 32 uninterrupted periods that typically last 2-8 days; (2) 56% of flares >X1 were caught, occurring in 19% of MFW days; (3) MFW periods ended at suitable times, but substantial gain could have been achieved in percentage of flares caught if periods had started 24 h earlier; (4) MFWs successfully forecast X-class flares with a true skill statistic (TSS) verification metric score of 0.500, that is comparable to a categorical flare/no-flare interpretation of the NOAA Space Weather Prediction Centre probabilistic forecasts (TSS = 0.488).Comment: 19 pages, 2 figures, accepted for publication in Solar Physic

Synoptic Hα Full-Disk Observations of the Sun from Big Bear Solar Observatory – I. Instrumentation, Image Processing, Data Products, and First Results

The Big Bear Solar Observatory (BBSO) has a long tradition of synoptic full-disk observations. Synoptic observations of contrast enhanced full-disk images in the Ca ii K-line have been used with great success to reproduce the H i Lα irradiance variability observed with the Upper Atmosphere Research Satellite (UARS). Recent improvements in data calibration procedures and image- processing techniques enable us now to provide contrast enhanced Hα full-disk images with a spatial resolution of approximately 2′′ and a temporal resolution of up to 3 frames min−1. In this first paper in a series, we describe the instruments, the data calibration procedures, and the image-processing techniques used to obtain our daily Hα full-disk observations. We also present the final data products such as low- and high-contrast images, and Carrington rotation charts. A time series of an erupting mini-filament further illustrates the quality of our Hα full-disk observations and motivate one of the future research projects. This lays a solid foundation for our subsequent studies of solar activity and chromospheric fine structures. The high quality and the sunrise- to-sunset operation of the Hα full-disk observations presented in this paper make them an ideal choice to study statistical properties of mini-filament eruptions, chromospheric differential rotation, and meridional flows within the chromosphere, as well as the evolution of active regions, filaments, flares, and prominences

Evaluation and recommendations for improving the accuracy of an inexpensive water temperature logger

Author Posting. © American Meteorological Society, 2013. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Atmospheric and Oceanic Technology 30 (2013): 1576–1582, doi:10.1175/JTECH-D-12-00204.1.Onset's HOBO U22 Water Temp Pros are small, reliable, relatively inexpensive, self-contained temperature loggers that are widely used in studies of oceans, lakes, and streams. An in-house temperature bath calibration of 158 Temp Pros indicated root-mean-square (RMS) errors ranging from 0.01° to 0.14°C, with one value of 0.23°C, consistent with the factory specifications. Application of a quadratic calibration correction substantially reduced the RMS error to less than 0.009°C in all cases. The primary correction was a bias error typically between −0.1° and 0.15°C. Comparison of water temperature measurements from Temp Pros and more accurate temperature loggers during two oceanographic studies indicates that calibrated Temp Pros have an RMS error of ~0.02°C throughout the water column at night and beneath the surface layer influenced by penetrating solar radiation during the day. Larger RMS errors (up to 0.08°C) are observed near the surface during the day due to solar heating of the black Temp Pro housing. Errors due to solar heating are significantly reduced by wrapping the housing with white electrical tape.This work is based on research supported by Awards USA 00002 and KSA 00011 made by King Abdullah University of Science and Technology (KAUST) and by the Ocean Sciences Division of the National Science Foundation under Grant OCE- 0548961.2014-01-0

Performance of Major Flare Watches from the Max Millennium Program (2001 – 2010)

The physical processes that trigger solar flares are not well understood and significant debate remains around processes governing particle acceleration, energy partition, and particle and energy transport. Observations at high resolution in energy, time, and space are required in multiple energy ranges over the whole course of many flares in order to build an understanding of these processes. Obtaining high-quality, co-temporal data from ground- and space- based instruments is crucial to achieving this goal and was the primary motivation for starting the Max Millennium program and Major Flare Watch (MFW) alerts, aimed at coordinating observations of all flares ≥X1 GOES X-ray classification (including those partially occulted by the limb). We present a review of the performance of MFWs from 1 February 2001 to 31 May 2010, inclusive, that finds: (1) 220 MFWs were issued in 3,407 days considered (6.5% duty cycle), with these occurring in 32 uninterrupted periods that typically last 2-8 days; (2) 56% of flares ≥X1 were caught, occurring in 19% of MFW days; (3) MFW periods ended at suitable times, but substantial gain could have been achieved in percentage of flares caught if periods had started 24 h earlier; (4) MFWs successfully forecast X-class flares with a true skill statistic (TSS) verification metric score of 0.500, that is comparable to a categorical flare/no-flare interpretation of the NOAA Space Weather Prediction Centre probabilistic forecasts (TSS = 0.488)

Infinite families of superintegrable systems separable in subgroup coordinates

A method is presented that makes it possible to embed a subgroup separable superintegrable system into an infinite family of systems that are integrable and exactly-solvable. It is shown that in two dimensional Euclidean or pseudo-Euclidean spaces the method also preserves superintegrability. Two infinite families of classical and quantum superintegrable systems are obtained in two-dimensional pseudo-Euclidean space whose classical trajectories and quantum eigenfunctions are investigated. In particular, the wave-functions are expressed in terms of Laguerre and generalized Bessel polynomials.Comment: 19 pages, 6 figure

Minimum Time Effect of Fish Oil on Arterial Stiffness - A Pilot Study

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Gas phase production of NHD2 in L134N

We show analytically that large abundances of NH2D and NHD2 can be produced by gas phase chemistry in the interiors of cold dense clouds. The calculated fractionation ratios are in good agreement with the values that have been previously determined in L134N and suggest that triply-deuterated ammonia could be detectable in dark clouds. Grain surface reactions may lead to similar NH2D and NHD2 enhancements but, we argue, are unlikely to contribute to the deuteration observed in L134N.Comment: 6 pages, 2 figures, uses psfig.sty and emulateapj.sty, to appear in Astrophysical Journal, vol 55

Variability and spectral classification of LMC giants: results from DENIS and EROS

We present the first cross-identifications of sources in the near-infrared DENIS survey and in the micro-lensing EROS survey in a field of about 0.5 square degrees around the optical center (OC) of the Large Magellanic Cloud. We analyze the photometric history of these stars in the EROS data base and obtain light-curves for about 800 variables. Most of the stars are long period variables (Miras and Semi-Regulars), a few Cepheids are also present. We also present new spectroscopic data on 126 asymptotic giant branch stars in the OC field, 30 previously known and 96 newly discovered by the DENIS survey. The visible spectra are used to assign a carbon- (C-) or oxygen-rich (O-rich) nature to the observed stars on the basis of the presence of molecular bands of TiO, VO, CN, C2. For the remaining of the stars we used the (J-Ks) color to determine whether they are O-rich or C-rich. Plotting Log(period) versus Ks we find three very distinct period-luminosity relations, mainly populated by Semi-Regular of type a (SRa), b (SRb) and Mira variables. Carbon-rich stars occupy mostly the upper part of these relations. We find that 65% of the asymptotic giant branch population are long period variables (LPVs).Comment: 9 pages, 7 figures, 4 tables (2 via CDS), accepted by A&A journa

Deuterated Ammonia in Galactic Protostellar Cores

We report on a survey of \nh2d towards protostellar cores in low-mass star formation and quiescent regions in the Galaxy. Twenty-three out of thirty-two observed sources have significant (\gsim 5\sigma) \nh2d emission. Ion-molecule chemistry, which preferentially enhances deuterium in molecules above its cosmological value of \scnot{1.6}{-5} sufficiently explains these abundances. NH2D/NH3 ratios towards Class 0 sources yields information about the ``fossil remnants'' from the era prior to the onset of core collapse and star formation. We compare our observations with predictions of gas-phase chemical networks.Comment: 16 Pages, 7 Figures, Accepted to Ap.J., to appear in the June 20, 2001 editio

Higher Order Quantum Superintegrability: a new "Painlev\'e conjecture"

We review recent results on superintegrable quantum systems in a two-dimensional Euclidean space with the following properties. They are integrable because they allow the separation of variables in Cartesian coordinates and hence allow a specific integral of motion that is a second order polynomial in the momenta. Moreover, they are superintegrable because they allow an additional integral of order $N>2$. Two types of such superintegrable potentials exist. The first type consists of "standard potentials" that satisfy linear differential equations. The second type consists of "exotic potentials" that satisfy nonlinear equations. For $N= 3$, 4 and 5 these equations have the Painlev\'e property. We conjecture that this is true for all $N\geq3$. The two integrals X and Y commute with the Hamiltonian, but not with each other. Together they generate a polynomial algebra (for any $N$) of integrals of motion. We show how this algebra can be used to calculate the energy spectrum and the wave functions.Comment: 23 pages, submitted as a contribution to the monographic volume "Integrability, Supersymmetry and Coherent States", a volume in honour of Professor V\'eronique Hussin. arXiv admin note: text overlap with arXiv:1703.0975