367 research outputs found
Obtaining cosmetic toilet soap, posessing improved consumer properties
A method for producing a cosmetic soap including natural ingredient and soap base. As a natural soap component used propylene glycolic extract of camomile, peppermint, or a mixture of the extract and the materials extracted from the crushed particle size of 1 to 2 mm, obtained by extracting the crushed raw material in the raw materials and the ratio of extractable extractant (1 : 10 – 1 : 20), at a temperature of 20–60?C for 10–50 minutes, and added in an amount of 1–4% by weight of the soap base
Application features of hexane diacid polycondensation products with diethylene triamine and resin acids in paper technology
Article examines the effectiveness of the reinforcing action for the first time received additives based on adipic acid with diethylenetriamine and tall oil rosin acids rosin. It was found that the synthesized polymers exhibit polyaminoamide hydrophobic properties due to the presence in their structure of resin acids . Strengthening effect of these compoundsis shown by introducing the structure of nitrogencontaining groups contribute to the formation of additional interfiber bonds. Tests have paper samples containing in their composition nitrogen compounds showed that hardening effect new synthesized polymers are not inferior to imported compound Melapret PAE / A, and hydrophobicity and the wet paper samples with the newly synthesized polymers exceed the value of these indicators for the paper samples containing imported analog
Discovery of Localized Regions of Excess 10-TeV Cosmic Rays
An analysis of 7 years of Milagro data performed on a 10-degree angular scale
has found two localized regions of excess of unknown origin with greater than
12 sigma significance. Both regions are inconsistent with gamma-ray emission
with high confidence. One of the regions has a different energy spectrum than
the isotropic cosmic-ray flux at a level of 4.6 sigma, and it is consistent
with hard spectrum protons with an exponential cutoff, with the most
significant excess at ~10 TeV. Potential causes of these excesses are explored,
but no compelling explanations are found.Comment: Submitted to PhysRevLet
Results from the Milagrito experiment
The Milagro water Cherenkov detector near Los Alamos, New Mexico is the first air shower detector capable of continuously monitoring the sky at energies between 500 GeV and 20 TeV. Preliminary results of the Milagro experiment are presented. A predecessor of the Milagro detector, Milagrito, was operational from February 1997 to May 1998. Milagrito consisted of 228 8″ photomultiplier tubes (PMTs) arranged in a grid with a 2.8 meter spacing and submerged in 1–2 meters of water. During its operation, Milagrito collected in excess of 9 billion events with a median energy of about 3 TeV. The detector’s sensitivity extends below 1 TeV for showers from near zenith. The results of an all sky search for the Milagrito data for both transient and DC sources will be presented, including the Crab Nebula and active galaxies Markarian 501 and 421, which are known sources of TeV gamma-rays. Also presented will be a study of the TeV emission from gamma ray bursts (GRBs) in Milagrito’s field of view detected by the BATSE experiment on the Compton Gamma-Ray Observatory
Milagro: A TeV gamma-ray monitor of the Northern Hemisphere Sky
A new type of very high energy (\u3e a few 100 GeV) gamma-ray observatory, Milagro, has been built with a large field of view of \u3e1 steradian and nearly 24 hours/day operation. Milagrito, a prototype for Milagro, was operated from February 1997 to May 1998. During the summer of 1998, Milagrito was dismantled and Milagro was built. Both detectors use a 80 m×60 m×8 mpond of water in which a 3 m×3 m grid of photomultiplier tubes detects the Cherenkov light produced in the water by the relativistic particles in extensive air showers. Milagrito was smaller and had only one layer of photomultipliers, but allowed the technique to be tested. Milagrito observations of the Moon’s shadow and Mrk 501 are consistent with the Monte Carlo prediction of the telescopes parameters, such as effective area and angular resolution. Milagro is larger and consists of two layers of photomultiplier tubes. The bottom layer detects penetrating particles that are used to reject the background of cosmic-ray initiated showers
Detection of 6 November 1997 ground level event by Milagrito
Solar Energetic Particles (SEPs) with energies exceeding 10 GeV associated with the 6 November 1997 solar flare/CME (coronal mass ejection) have been detected with Milagrito, a prototype of the Milagro Gamma Ray Observatory. While SEP acceleration beyond 1 GeV is well established, few data exist for protons or ions beyond 10 GeV. The Milagro observatory, a ground based water Cherenkov detector designed for observing very high energy gamma ray sources, can also be used to study the Sun. Milagrito, which operated for approximately one year in 1997/98, was sensitive to solar proton and neutron fluxes above ∼4 GeV. In its scaler mode, Milagrito registered a rate increase coincident with the 6 November 1997 ground level event observed by Climax and other neutron monitors. A preliminary analysis suggests the presence of \u3e10 GeV particles
First Results of a Study of TeV Emission from GRBs in Milagrito
Milagrito, a detector sensitive to gamma-rays at TeV energies, monitored the
northern sky during the period February 1997 through May 1998. With a large
field of view and high duty cycle, this instrument was used to perform a search
for TeV counterparts to gamma-ray bursts. Within the Milagrito field of view 54
gamma-ray bursts at keV energies were observed by the Burst And Transient
Satellite Experiment (BATSE) aboard the Compton Gamma-Ray Observatory. This
paper describes the results of a preliminary analysis to search for TeV
emission correlated with BATSE detected bursts. Milagrito detected an excess of
events coincident both spatially and temporally with GRB 970417a, with chance
probability within the BATSE error radius. No other
significant correlations were detected. Since 54 bursts were examined the
chance probability of observing an excess with this significance in any of
these bursts is . The statistical aspects and physical
implications of this result are discussed.Comment: 6 pages, 5 figures, to appear in "GeV-TeV Astrophysics: Toward a
Major Atmospheric Cherenkov Telescope VI," Snowbird, Utah (August, 1999
First results of a study of TeV emission from GRBs in Milagrito
Milagrito, a detector sensitive to γ-rays at TeV energies, monitored the northern sky during the period February 1997 through May 1998. With a large field of view and high duty cycle, this instrument was used to perform a search for TeV counterparts to γ-ray bursts. Within the Milagrito field of view 54 γ-ray bursts at keV energies were observed by the Burst And Transient Satellite Experiment (BATSE) aboard the Compton Gamma-Ray Observatory. This paper describes the results of a preliminary analysis to search for TeV emission correlated with BATSE detected bursts. Milagrito detected an excess of events coincident both spatially and temporally with GRB 970417a, with chance probability 2.8×10−5 within the BATSE error radius. No other significant correlations were detected. Since 54 bursts were examined the chance probability of observing an excess with this significance in any of these bursts is 1.5×10−3. The statistical aspects and physical implications of this result are discussed
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