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A new application for x-ray lithography: Fabrication of blazed diffractive optical elements with a deep phase profile
Use of x-ray lithography to produce blazed diffractive optical elements (DOEs) is described. Proposed method allows one to make highly efficient blazed DOE with a deep phase profile (ten wavelengths and more) using a single x-ray mask with a binary transmission pattern. Unlike the well-known multilevel DOEs, blazed ones do not involve fabrication and aligning of a set of masks. DOEs with a profile depth of 10 {mu}m and more and zone sizes down to 1 {mu}m can be obtained due to the short wavelength and high penetrability of x rays. The first experimental samples of blazed DOEs with a 10 {mu}m-height profile--lenses and gratings - were fabricated by x-ray lithography with synchrotron radiation using the x-ray masks, prepared in accordance with the pulse-width modulation algorithm. Diffraction efficiency for lenses was measured for white light: it is higher than 80% for the central part of the lenses (inside a 10 mm diameter) and about 60% for an area of 20 mm diameter
The optical identifcation of events with poorly defined locations: The case of the Fermi GBM GRB140801A
We report the early discovery of the optical afterglow of gamma-ray burst
(GRB) 140801A in the 137 deg 3- error-box of the Fermi Gamma-ray
Burst Monitor (GBM). MASTER is the only observatory that automatically react to
all Fermi alerts. GRB 140801A is one of the few GRBs whose optical counterpart
was discovered solely from its GBM localization. The optical afterglow of GRB
140801A was found by MASTER Global Robotic Net 53 sec after receiving the
alert, making it the fastest optical detection of a GRB from a GBM error-box.
Spectroscopy obtained with the 10.4-m Gran Telescopio Canarias and the 6-m BTA
of SAO RAS reveals a redshift of . We performed optical and
near-infrared photometry of GRB 140801A using different telescopes with
apertures ranging from 0.4-m to 10.4-m. GRB 140801A is a typical burst in many
ways. The rest-frame bolometric isotropic energy release and peak energy of the
burst is erg and
keV, respectively, which is consistent with the
Amati relation. The absence of a jet break in the optical light curve provides
a lower limit on the half-opening angle of the jet deg. The
observed is consistent with the limit derived from the
Ghirlanda relation. The joint Fermi GBM and Konus-Wind analysis shows that GRB
140801A could belong to the class of intermediate duration. The rapid detection
of the optical counterpart of GRB 140801A is especially important regarding the
upcoming experiments with large coordinate error-box areas.Comment: in press MNRAS, 201
Determination of fission barrier height of Fr 210 and Ra 210 via neutron measurement
Fission barrier heights of short-lived nuclei away from line of β stability are not known reliably. Low-energy fission of Fr210 and Ra210, produced by (d,p) and (d,n) transfer reaction on the re-accelerated unstable beam Fr209 was investigated at HIE-ISOLDE. Four Timepix3 pixel detectors were installed on the body of the ACTAR TPC demonstrator chamber. Polyethylene converters were used for the detection of fast neutrons. Since no significant background was observed, it was possible to measure the spatial distribution of emitted neutrons reflecting the fission excitation function. Subsequent simulations employing the results of the talys code and available data on fission fragment distributions allowed to estimate directly the value of the fission barrier height for the neutron-deficient nucleus Fr210. This first direct measurement confirmed the reduction of the fission barrier compared to available theoretical calculations by 15-30%
ЭПЛАН (МАЗЬ, РАСТВОР) – НОВЫЙ ПРЕПАРАТ ДЛЯ МЕСТНОГО ЛЕЧЕНИЯ ИНФЕКЦИИ КОЖИ И МЯГКИХ ТКАНЕЙ В МНОГОПРОФИЛЬНОМ СТАЦИОНАРЕ
The paper presents the results of a multicenter postmarketing clinical laboratory study of Eplan ointment and eplan solution for the topical treatment of skin and soft tissue infections in outpatient, inpatient, and field settings. The results of the study in 793 patients with skin and soft tissue infections of different locations and genesis demonstrate the high clinical efficacy of the medicaments along with their easy-to-use formulation and economic availability. В статье представлены результаты постмаркетингового многоцентрового клинико-лабораторного исследования препаратов Эплан мазь и Эплан раствор, предназначенных для местного лечения инфекции кожи и мягких тканей (ИКМТ) в амбулаторных, стационарных и военно-полевых условиях. Результаты проведенного исследования у 793 больных с ИКМТ различной локализации и генеза демонстрируют высокую клиническую эффективность препаратов наряду с их удобной лекарственной формой и экономической доступностью.
Ранние оптические наблюдения семи гамма-всплесков в сравнении с их гамма-рентгеновскими характеристиками на глобальной сети телескопов-роботов МГУ МАСТЕР
Seven gamma-ray bursts – GRB 130907A, GRB 140311B, GRB 140129B, GRB 160227A, GRB 120404A, GRB 110801A, and GRB 120811C were observed by the MSU MASTER (Mobile Astronomical System of TElescope Robots) Global Network. Full automation of the observations provided for obtaining unique data on the properties of early optical radiation accompanying gamma-ray bursts. The data are compared in the optical (MASTER), X-ray (SWIFT X-ray Telescope, XRT) and gamma (SWIFT Burst Alert Telescope, BAT) ranges. Based on the data obtained, two groups are identified, and their radiation mechanisms are revealed. The effect of gamma-ray bursts on the biosphere of the Earth is determined, and the estimates and the scale of such an effect are considered.В статье представлены результаты наблюдений семи гамма-всплесков – GRB 130907A, GRB 140311B, GRB 140129B, GRB 160227A, GRB 120404A, GRB 110801A, GRB 120811C, полученные на телескопах-роботах глобальной сети МГУ «МАСТЕР». Полная автоматизация наблюдений позволила получить уникальные данные о свойствах раннего оптического излучения, сопровождавшего гамма-всплески. Выполнено сравнение данных в оптическом (МАСТЕР), рентгеновском (SWIFTX-rayTelescope (XRT)) и гамма (SWIFTBurstAlertTelescope (BAT)) диапазонах. На основании полученных данных выделены две группы, для которых определен механизм излучения. Также определено воздействие гамма-всплесков на биосферу Земли и рассмотрены оценки и масштаб такого влияния
Application of the Shack–Hartmann Wavefront Sensor for Monitoring the Parameters of a Supersonic Gas Jet
Improvement of metrological characteristics of laser image generators with circular scanning
Method of Compensating for Trajectory Distortions of Relative Motion of the Writing Beam in Laser Image Generators with Circular Scanning
Microstructuring of optical surfaces: Technology and device for direct laser writing of diffractive structures
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