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Thousands of photos and illustrations, hundreds of animations and videos, quizzes to test your knowledge, daily medical news, medical self-assessments, social media. Featured content. Ketamine as an Antidepressant—Commentary. It has been well-established that the administration of sub-anesthetic doses of ketamine often has marked antidepressant effects among patients with treatment-resistant depression TRD. Glenn D. Many epidemiological studies have established a relationship between elevated LDL-cholesterol LDL-C levels and an increased risk of ischemic thrombotic stroke as well as coronary artery Crohn Disease.
Aaron E. Crohn disease is a chronic transmural inflammatory bowel disease that usually affects the distal ileum and colon but may occur in any part of the GI tract. Symptoms include diarrhea and abdominal Videos View All. The SXS observed an unprecedented spectrum, revealing a landscape of X-ray peaks emitted from various chemical elements with a resolution some 30 times better than previously seen.
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After all, clusters represent an average chemical distribution from many types of stars in many types of galaxies that formed long before the Sun. The resulting spectrum has 30 times the detail of any previously captured, revealing many X-ray peaks associated with chromium, manganese, nickel and iron.
These blasts are thought to be responsible for producing most of the universe's chromium, manganese, iron and nickel — metals collectively known as "iron-peak" elements. Although stable on its own, a white dwarf can undergo a runaway thermonuclear explosion if it's paired with another object as part of a binary system.
This occurs either by merging with a companion white dwarf or, when paired with a nearby normal star, by stealing some of partner's gas. The transferred matter can accumulate on the white dwarf, gradually increasing its mass until it becomes unstable and explodes. Different masses produce different amounts of iron-peak metals, so a detailed tally of these elements over a large region of space, like the Perseus galaxy cluster, could indicate which kinds of white dwarfs blew up more often.
This means both the solar system and the Perseus cluster experienced broadly similar chemical evolution, suggesting that the processes forming stars — and the systems that became Type Ia supernovas — were comparable in both locations. One of its instruments will have capabilities similar to the SXS flown on Hitomi. This is a surprise because the Perseus cluster is home to NGC , a highly energetic active galaxy. Once this technique can be extended to other clusters, it will allow cosmologists to use them as better probes of our models of the Universe's evolution from the Big Bang to the present time.
It was therefore the best choice to fully demonstrate the power of the SXS Soft X-ray Spectrometer , an X-ray micro-calorimeter that promised to deliver an unprecedented accuracy in the reconstruction of the energy of the incoming X-ray photons.
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But it was the absolute velocity of the gas that took them by surprise. This demonstrates that the technology of X-ray micro-calorimeters can yield truly transformational results," says Guainazzi. Turbulent motions in a fluid are part of our everyday life, as airplane passengers, swimmers, or parents filling a bathtub all experience. The study of such chaotic behavior is also a powerful tool for astronomers to understand the behavior of celestial objects.
This is extraordinary considering that the active galaxy NGC sits at the heart of the cluster. It is pumping jetted energy into its surroundings, creating bubbles of extremely hot gas.
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It was thought that these bubbles induce turbulence, which keeps the central gas hot. The affected employees are as follows: Unfortunately, based on the rigorous technical investigation, the following conclusions were made: However, the project came to the conclusion that the received signals were not from ASTRO-H due to the differences in frequencies as a consequence of technological study.
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The project will carefully review all phases from design, manufacturing, verification, and operations to identify the causes that may have led to this anomaly including background factors. In the result, the Reaction Wheel RW to stop the rotation was activated and lead to the rotation of satellite. The angular momentum kept accumulating in RW. At this time ACS provided atypical command to the thrusters by the inappropriate thruster control parameters.
As a result, it thrusted in an unexpected manner, and it is estimated that the satellite rotation was accelerated. Table 2: 1. Presumed Mechanism Summary. After that by the correction using STT data, the value converges within normal one. So it is estimated that the attitude was controlled based on the false determination value of attitude.
Figure 2. Presumed mechanism from the "Normal Status" to "Objects separation". In the result, the RW Reaction Wheel to stop the rotation was activated and lead to the rotation of satellite.
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As the result, the rotation continued. A sun sensor is not used for this purpose. Table 4: Presumed Mechanism 2: From the attitude anomaly to the continuously rotation of attitude. This indicates the possibility of insufficient verification of the process from creating the parameter to setting it on the satellite. This situation is under investigation.
Figure Presumed mechanism 3: From the attitude rotation to the rotation anomaly. JAXA continues the investigation to estimate the satellite status and recover its operation. Through the investigation, JAXA has recognized the following situation. JAXA estimates that it is not depleted for now as of April 15th. Table 5: Presumed mechanism 4: From attitude rotation anomaly to the object separation. JAXA is going to work through the following tasks in parallel. The project was scheduled to proceed with the calibration phase in the middle of April.
All the telemetry data including non-visible time have been obtained till USC operation, which ends at on March Figure Hitomi Sequence of Events. In the effort of obtaining the telemetry data from Hitomi, JAXA continues to send the command to the estimated trajectory. JAXA believes it is likely that these signals came from Hitomi. Table 7: Status of Hitomi operation after anomaly. That shows that the two objects are from the Hitomi satellite. JAXA is making the best effort for establishing the communication with Hitomi by sending the radio signals with commands by using the most possible chances of JAXA ground stations in Japan as well as in foreign countries.
Table 9: Current operation for recovery and fault analysis Ref. Up to now, JAXA has not been able to figure out the state of health of the satellite. While the cause of communication failure is under investigation, JAXA received short signal from the satellite, and is working for recovery. The headquarters held its first meeting today, and has been working for recovery and the investigation of the cause. With this confirmation, the critical operation phase of Hitomi is completed.
The team then confirmed that it reached the absolute temperature of 50 millidegrees 0.
The satellite is currently in good health. A non-focusing detector will also cover the soft gamma-ray range up to keV SGD. The FOVs and effective areas of these instruments are shown in Figures 16 and The simultaneous broad bandpass, coupled with high spectral resolution, will enable the pursuit of a wide variety of important science themes. The result obtained with SXT-2 exceeds the desired goal. In order to collect more photons, SXT-2, which has a slightly better angular resolution, will be used for the SXS, because it has a smaller detector area.
It is composed of thin reflector shells tightly nested confocally and coaxially. A conical approximation of Wolter-I type optics is used. Stray light, or contaminating X-rays from outside of the field of view, is reduced by a stray-light baffle, which consists of coaxially-nested cylindrical aluminum blades placed above each reflector. A thermal shield is attached in front of the pre-collimator to stabilize the thermal environment of the SXT.
Japanese Astro-E2 Satellite Launched
The shield is made of Al-coated polyimide film to ensure a large effective area in the soft energy band. The XCS is placed at the focal length of 5. The effective area is optimized at high energies, with cm 2 at 6 keV, 50 cm 2 at 0. The energy range will span from 0. In contrast to gratings, the spectral power increases as a function of energy. With microcalorimetry, X-ray photons strike the detector's absorbers and their energy is converted to heat, which a thermometer then measures.
The heat is directly proportional to the X-ray's energy, which can reveal much about the physical properties of the object emitting the radiation.
To measure as many X-ray photons as possible, Richard Kelly and hid GSFC team placed an array of microcalorimeter detectors at the focus of a large X-ray telescope. The detector package and cooling system then were placed inside a dewar. The XCS will also carry a suite of filters: X-ray filters to attenuate the X-ray signal for bright X-ray sources one Be-type to block the low-energy photons and one neutral density for very bright sources and background calibration , and one polyimide filter to avoid contamination in early phases of the mission.