5,323 research outputs found
Improved Astrometry and Photometry for the Luyten Catalog. I. Bright Stars
We outline the construction of an updated version of the New Luyten
Two-Tenths (NLTT) catalog of high proper motion stars, which will contain
improved astrometry and photometry for the vast majority of the ~59,000 stars
in NLTT. The bright end is constructed by matching NLTT stars to Hipparcos,
Tycho-2, and Starnet; the faint end by matching to USNO-A and 2MASS. In this
first paper, we detail the bright-end matching procedure. We show that for the
majority of stars in his catalog, Luyten measured positions accurate to 1" even
though he recorded his results much more coarsely. However, there is a long
tail of position errors, with one error as large as 11 deg. Proper-motion
errors for the stars with small position errors are 24 mas/yr (1 sigma) but
deteriorate to 34 mas/yr for stars with inferior positions. NLTT is virtually
100% complete for V15 deg, but completeness in this magnitude
range falls to about 75% at the Galactic plane. Incompleteness near the plane
is not uniform, but is rather concentrated in the interval -80<l<20, where the
Milky Way is brightest.Comment: Submitted to ApJ, 28 pages including 7 figure
No nearby counterparts to the moving objects in the Hubble Deep Field
Ibata et al (1999) have recently discovered faint, moving objects in the
Hubble Deep Field. The quantity, magnitudes and proper motions of these objects
are consistent with old white dwarfs making up the Galactic dark halo. We
review a number of ground-based proper motion surveys in which nearby dark halo
white dwarfs might be present, if they have the colours and absolute magnitudes
proposed. No such objects have been found, whereas we argue here that several
times more would be expected than in the Hubble Deep Field. We conclude it is
unlikely that hydrogen atmosphere white dwarfs make up a significant fraction
of the halo dark matter. No limits can be placed yet on helium atmosphere
dwarfs from optical searches.Comment: 7 pages, 4 figures, MNRAS LaTeX forma
High-Resolution Imaging and Optical Control of Bose-Einstein Condensates in an Atom Chip Magnetic Trap
A high-resolution projection and imaging system for ultracold atoms is
implemented using a compound silicon and glass atom chip. The atom chip is
metalized to enable magnetic trapping while glass regions enable high numerical
aperture optical access to atoms residing in the magnetic trap about 100
microns below the chip surface. The atom chip serves as a wall of the vacuum
system, which enables the use of commercial microscope components for
projection and imaging. Holographically generated light patterns are used to
optically slice a cigar-shaped magnetic trap into separate regions; this has
been used to simultaneously generate up to four Bose-condensates. Using
fluorescence techniques we have demonstrated in-trap imaging resolution down to
2.5 micronsComment: 4 pages, 5 figures, 12 reference
Optimized bio-inspired kernels with twin support vector machine using low identity sequences to solve imbalance multiclass classification
The function of enzymes is performed differently depending on their bio-chemical mechanisms and important to the prediction of protein structure and function. In order to overcome the weaknesses of imbalance data distribution in subclasses prediction we proposed Bio-Twin Support Vector Machine (Bio–TWSVM). The TWSVM approach as also allow for kernel optimization where in this study we have introduced the bio-inspired kernels such as the Fisher, spectrum and mismatch kernels which at the same time incorporate the biological information regarding the protein evolution in the classification process
Nearby Microlensing Events - Identification of the Candidates for the SIM
The Space Interferometry Mission (SIM) is the instrument of choice when it
comes to observing astrometric microlensing events where nearby, usually
high-proper-motion stars (``lenses''), pass in front of more distant stars
(``sources''). Each such encounter produces a deflection in the source's
apparent position that when observed by SIM can lead to a precise mass
determination of the nearby lens star. We search for lens-source encounters
during the 2005-2015 period using Hipparcos, ACT and NLTT to select lenses, and
USNO-A2.0 to search for the corresponding sources, and rank these by the SIM
time required for a 1% mass measurement.
For Hipparcos and ACT lenses, the lens distance and lens-source impact
parameter are precisely determined so the events are well characterized. We
present 32 candidates beginning with a 61 Cyg A event in 2012 that requires
only a few minutes of SIM time. Proxima Centauri and Barnard's star each
generate several events. For NLTT lenses, the distance is known only to a
factor of 3, and the impact parameter only to 1''. Together, these produce
uncertainties of a factor ~10 in the amount of SIM time required. We present a
list of 146 NLTT candidates and show how single-epoch CCD photometry of the
candidates could reduce the uncertainty in SIM time to a factor of ~1.5.Comment: ApJ accepted, 31 pages (inc. 5 tables), 5 figures. t SIM refine
KEKERASAN PERSEKUSI MENURUT UNDANG-UNDANG NOMOR 39 TAHUN 1999 TENTANG HAK ASASI MANUSIA
Tujuan dilakukannya penelitian ini adalah untuk mengetahui bagaimanakah ketentuan-ketentuan kekerasan persekusi menurut hukum pidana dan bagaimanakah perlindungan HAM terhadap korban kekerasan persekusi, di mana dengan mnggunakan metode penelitian hukum normatif disimpulkan bahwa: 1. Kekerasan persekusi adalah bentuk-bentuk kekerasan yang berintikan pada penganiayaan dalam segala bentuk dan macamnya yang oleh KUHP dan berbagai instrumen HAM Nasional ditentukan sebagai tindak pidana yang pelakunya bersifat individual (orang-perorangan), sedangkan dalam Instrumen HAM Internasional, lebih bersifat massal yang dilakukan secara sistematis dan meluas. 2. Perlindungan hukum dan HAM terhadap korban kekerasan persekusi selain dibebaninya kewajiban dan tanggung jawab hukum bagi pelakunya maka bagi korban kekerasan persekusi lebih dilindungi hak-haknya sebagai HAM.Kata kunci: persekusi, kekerasa
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