85,176 research outputs found
DIRBE Minus 2MASS: Confirming the Cosmic Infrared Background at 2.2 Microns
Stellar fluxes from the 2MASS catalog are used to remove the contribution due
to Galactic stars from the intensity measured by DIRBE in four regions in the
North and South Galactic polar caps. After subtracting the interplanetary and
galactic foregrounds, a consistent residual intensity of 14.8 +/- 4.6 kJy/sr or
20.2 +/- 6.3 nW/m^2/sr at 2.2 microns is found. At 1.25 microns the residuals
show more scatter and are a much smaller fraction of the foreground, leading to
a weak limit on the CIRB of 12.0 +/- 6.8 kJy/sr or 28.9 +/- 16.3 nW/m^2/sr (1
sigma).Comment: ApJ in press. 14 pages Latex with 7 included figures. accepted
version with 1 new figur
COBE Observations of the Cosmic Infrared Background
The Diffuse InfraRed Background Experiment on COBE measured the total
infrared signal seen from space at a distance of 1 astronomical unit from the
Sun. Using time variations as the Earth orbits the Sun, it is possible to
remove most of the foreground signal produced by the interplanetary dust cloud
[zodiacal light]. By correlating the DIRBE signal with the column density of
atomic hydrogen measured using the 21 cm line, it is possible to remove most of
the foreground signal produced by interstellar dust, although one must still be
concerned by dust associated with H_2 (molecular gas) and H II (the warm
ionized medium). DIRBE was not able to determine the CIRB in the 5-60 micron
wavelength range, but did detect both a far infrared background and a near
infrared background. The far infrared background has an integrated intensity of
about 34 nW/m^2/sr, while the near infrared and optical extragalactic
background has about 59 nW/m^2/sr. The Far InfraRed Absolute Spectrophotometer
(FIRAS) on COBE has been used to constrain the long wavelength tail of the far
infrared background but a wide range of intensities at 850 microns are
compatible with the FIRAS data. Thus the fraction of the CIRB produced by SCUBA
sources has large uncertainties in both the numerator and the denominator.Comment: Invited paper presented at the 2nd VERITAS Symposium on TeV
Astrophysics of Extragalactic Sources, April 24-26, 2003 at the Adler
Planetarium in Chicago. 8 pages LaTeX with 3 embedded figure
Hadwiger Integration of Random Fields
Hadwiger integrals employ the intrinsic volumes as measures for integration
of real-valued functions. We provide a formula for the expected values of
Hadwiger integrals of Gaussian-related random fields. The expected Hadwiger
integrals of random fields are both theoretically interesting and potentially
useful in applications such as sensor networks, image processing, and cell
dynamics. Furthermore, combining the expected integrals with a functional
version of Hadwiger's theorem, we obtain expected values of more general
valuations on Gaussian-related random fields
Programmed multiplexing system simultaneously monitors several voltages
System consists of digital voltmeter with binary coded decimal output, programmer, multiplexer, and two to six gated digital displays. Maximum number of circuits monitored is determined by digital voltmeter, rate of change of parameter being measured and complexity of multiplexer design
The Intersection between Chickering’s Theory and Generation Z Student of Color Activism
Student activism is an ever-developing trend on college campuses. The current generation, Generation Z, started college in 2013. Analyzing literature on student development and how it intersects with the student activist identity reveals what institutions can do to further serve students in a generational context. When characteristics of students from Generation Z are given proper attention, campus administrators can better understand student activism as an identity. As current and new generations matriculate through college, institutions need to continuously challenge their processes and recreate equitable and inclusive spaces for their students
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