USAP-DC

{"dp_type": "Dataset", "free_text": "Cosmos"}

[{"awards": "0632399 Jefferies, Stuart", "bounds_geometry": ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"], "date_created": "Fri, 01 Jan 2016 00:00:00 GMT", "description": "The ultimate goal of this project is to determine the structure and dynamics of the Sun\u0027s atmosphere, assess the role of MHD waves in heating the chromosphere/corona and driving the solar wind, and better understand how the Sun\u0027s atmosphere couples to the solar interior. As the solar atmosphere is \u0027home\u0027 to many of the solar phenomena that can have a direct impact on the biosphere, including flares, coronal mass ejections, and the solar wind, the broader impact of such studies is that they will lead to an improved understanding of the Sun-Earth connection. \nUnder the current award we have developed a suite of instruments that can simultaneously image the line-of-sight Doppler velocity and longitudinal magnetic field at four heights in the solar atmosphere at high temporal cadence. The instruments use magneto-optical filters (see Cacciani, Moretti and Rodgers, Solar Physics 174, p.115, 2004) tuned to the solar absorption lines at 422 nm (Ca I), 589 nm (Na D2), 770 nm (K) and 1083 nm (He). These lines sample the solar atmosphere from the mid-photosphere to the high-chromosphere. \nA proof-of-concept run was made in the Austral summer of 2007/2008 using the Na and K versions of the instruments. Here we recorded over 40 hours of full-disk, intensity images of the Sun in the red and blue wings of the Na and K Fraunhofer lines, in both right- and left-circularly polarized light. The images were obtained at a rate of one every five seconds with a nominal spatial resolution of 4 arc-seconds. The run started at 09:44 UT on February 2, 2008 and ended at 03:30 UT on February 4, 2008.\nData Quality Assessment:\nThe temperature controls of the instrument housings were unable to fully compensate for the harse Antartic winds encountered during the observing run. This led to large (~15 C) temperature swings which adversely affected the instruments (and thus data quality) in two ways: 1) Crystals of Na and K were deposited on the magneto-optical filter windows leading to \"hot spots\" in the images. These \"hot spots\" come and go with time as the temperature changes. 2) The changing temperature caused the optical rails to contract and expand causing the final images to go in- and out-of-focus, thus reducing the resolution to greater than 4 arc-seconds. Both these effect are worse in the K data.\nDespite these problems, the intensity images can be combined to provide magnetic images that show a very high sensitivity (\u003c 5 Gauss in a 5 second integration).\nData Description:\nThe raw data are stored as a series of 1024x1024x4 FITS images. The format is: blue image (left circulary polarized light), blue image (right circularly polarized light), red image (left circulary polarized light), red image (right circularly polarized light).\nThe naming convention for the images is: Type_Instrument_Day_hour_minutes_seconds\nwhere Type is I (intensity), F (flatfield), D (dark)\n Instrument is 0 (Na), 1 (K)\n Day is the day number from the beginning of the year where January 1 is day 0\nFor example, I_0_32_12_34_40.fits is an intensity image taken with the Na instrument at 12:34.40 UT on February 2, 2008.\nNotes: \n1) The flatfield images were acquired by moving a diffuser in front of the Sun during the integration. The resulting images therefore have to be corrected for residual low-spatial frequencies due to the non-flat nature of the light source.\n2) Each FITS file header contains a variety of information on the observation, e.g.,\nF_CNTO\t: number of summed frames in each 5 second integration (*)\nFPS\t\t: Camera frame rate (Frames Per Second)\nFLIP\t: Rate at which the half-wave rotator (magnetic switch) was switched\nINT_PER\t: Integration time (in seconds)\nMOF\t\t: Temperature of magneto-optical filter cell\nWS\t\t: Temperature of wing selector cell\nTEMP_0\t: Temperature of camera 0\nTEMP_1\t: Temperature of camera 1\nTEMP_2\t: Temperature inside instrument (location 1)\nTEMP_3\t: Temperature of narrowband filter\nTEMP_5\t: Temperature of magnets surrounding MOF cell\nTEMP_6\t: Temperature inside instrument (location 2)\nTEMP_7\t: Temperature of housing for magnetic switch\n(*) This is the frame count for the camera. The number of frames in each image for the two different polarization states, is half this number.\nThe measured temperatures are only coarse measurements.\n3) Due to reflection in the final polarizing beam splitter (which separates the \"red\" and \"blue\" signals into the two cameras), the camera 1 data need to \"reversed\" along the x-axis (i.e. listed as [1024:1] instead of [1:1024])\n4) Line-of-sight velocity and magnetic field images are generated from the observed intensity images. Doppler images as (red-blue)/(red+blue), magnetic images as the difference between the Doppler images\nfor right- and left-circularly polarized light.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Cosmos; Satellite Remote Sensing; Sun", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": null, "persons": "Jefferies, Stuart M.", "project_titles": "Tomographic Imaging of the Velocity and Magnetic Fields in the Sun\u0027s Atmosphere", "projects": [{"proj_uid": "p0000526", "repository": "USAP-DC", "title": "Tomographic Imaging of the Velocity and Magnetic Fields in the Sun\u0027s Atmosphere"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Tomographic Imaging of the Velocity and Magnetic Fields in the Sun\u0027s Atmosphere", "uid": "600152", "west": -180.0}, {"awards": "0838838 Evenson, Paul", "bounds_geometry": ["POLYGON((-165.89 -56.02,-150.571 -56.02,-135.252 -56.02,-119.933 -56.02,-104.614 -56.02,-89.295 -56.02,-73.976 -56.02,-58.657 -56.02,-43.338 -56.02,-28.019 -56.02,-12.7 -56.02,-12.7 -58.203,-12.7 -60.386,-12.7 -62.569,-12.7 -64.752,-12.7 -66.935,-12.7 -69.118,-12.7 -71.301,-12.7 -73.484,-12.7 -75.667,-12.7 -77.85,-28.019 -77.85,-43.338 -77.85,-58.657 -77.85,-73.976 -77.85,-89.295 -77.85,-104.614 -77.85,-119.933 -77.85,-135.252 -77.85,-150.571 -77.85,-165.89 -77.85,-165.89 -75.667,-165.89 -73.484,-165.89 -71.301,-165.89 -69.118,-165.89 -66.935,-165.89 -64.752,-165.89 -62.569,-165.89 -60.386,-165.89 -58.203,-165.89 -56.02))"], "date_created": "Fri, 01 Jan 2010 00:00:00 GMT", "description": "We determined a set of cosmic ray response functions for the ice Cherenkov detector used by the surface air shower IceTop, part of the IceCube Neutrino Observatory at the South Pole. At the same time we measured the response function of moderated neutron detectors that are now in use in conjunction with IceTop. We did this by means of a global latitude survey conducted with a detector identical to the IceTop sensors built in a freezer van installed on the Swedish icebreaker Oden. The freezer van also housed the moderated neutron detectors. Cosmic rays shower data were recorded on the Oden voyage from Sweden to McMurdo and return during the 2009-2010 austral summer season. Reliance on student observers and data analysts enhanced the broader impact of this research and firmly grounds this effort in its educational mission.", "east": -12.7, "geometry": ["POINT(-89.295 -66.935)"], "keywords": "Antarctica; Atmosphere; Cosmic Ray; Cosmos; Icecube; Oden; Southern Ocean", "locations": "Southern Ocean; Antarctica", "north": -56.02, "nsf_funding_programs": null, "persons": "Tilav, Serap; Evenson, Paul; Bieber, John; Clem, John", "project_titles": "Collaborative Research: Measurement of Cosmic Ray Response Functions for an Ice Cherenkov Detector", "projects": [{"proj_uid": "p0000516", "repository": "USAP-DC", "title": "Collaborative Research: Measurement of Cosmic Ray Response Functions for an Ice Cherenkov Detector"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.85, "title": "Measurement of Cosmic Ray Response Functions for an Ice Cherenkov Detector", "uid": "600098", "west": -165.89}, {"awards": "0538683 Lal, Devendra", "bounds_geometry": ["POINT(-180 -90)"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "The principal aim of this research is to determine the precise manner in which solar activity has varied in the past 1000 years. During this period, four periods of very low solar activity have been identified: Wolf (1305-1345 AD), Spoerer (1418-1540 AD), Maunder (1645-1715), and one period of high solar activity (1100-1250 A.D.) have been deduced based on available historical records of sunspot numbers and aurora. Our proposal aims to study the solar activity during the past 1000 years in detail using a new method, based on studies of polar ice, as developed earlier (Earth and Planetary Science Letters, 234, 335-349, 2005). The method is based on the fact that greater solar activity leads to production of greater magnetic fields in the heliosphere, which reduces the primary cosmic ray flux in the near Earth environment, and vice-versa. Consequently if one can measure the primary cosmic ray flux in the near Earth space, it becomes a direct measure of the solar activity. Lal et al. (Earth and Planetary Science Letters, 234, 335-349, 2005) concluded that the best way of measuring the primary cosmic ray flux would be to measure the concentration of cosmogenic in-situ produced 14C in polar ice sheets, which was discovered by Lal et al. (Nature 346, 350-352, 1990). Following this idea Lal et al. (op. cit.) measured cosmogenic in-situ produced in 19 samples from the GISP 2 core covering time range of 375-31,250 yrs B.P. Their studies showed that there were two periods of very low solar activity in this time bracket (during 8500-9500 B.P and 27,000-32,000 B.P.), and one high solar activity period during 12,000-16,000 yrs B.P. In order to provide an independent check on the veracity of the new method, we decided to apply it to the historical period, \u003c 1000 yrs B.P. The inferred Solar activities based on the study of cosmogenic in-situ produced 14C in South Pole ice samples clearly establish that there was a period of high Solar activity during 1100-1250 A.D., and a period of very low solar activity during 1416-1534 A.D, designated as the Spoerer Minimum. These results however do not confirm the proposed dates for the Dalton and the Maunder Minimum periods, predicted to be 1795-1825 A.D. and 1654-1714 A.D. respectively. Instead, our studies show that there was a long duration period of low solar activity during 1750-1860 A.D. These results make it quite clear that we should carry out more studies to fully establish the temporal behavior of the Solar activity in the past 1000 yrs.", "east": -180.0, "geometry": ["POINT(-180 -90)"], "keywords": "Antarctica; Carbon-14; Cosmos; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Solar Activity; South Pole", "locations": "South Pole; Antarctica", "north": -90.0, "nsf_funding_programs": null, "persons": "Lal, Devendra", "project_titles": "Solar Activity during the Last Millennium, Estimated from Cosmogenic in-situ 14C in South Pole and GISP2 Ice Cores", "projects": [{"proj_uid": "p0000555", "repository": "USAP-DC", "title": "Solar Activity during the Last Millennium, Estimated from Cosmogenic in-situ 14C in South Pole and GISP2 Ice Cores"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Solar activity during the last millennium, estimated from cosmogenic in-situ C14 in South Pole and GISP2 ice cores", "uid": "600058", "west": -180.0}, {"awards": "0636899 Mende, Stephen", "bounds_geometry": null, "date_created": "Tue, 01 Jan 2008 00:00:00 GMT", "description": "Auroral protons are not energized by electric fields directly above the auroral atmosphere and therefore they are a much better diagnostic of processes deep in the magnetosphere. It has been shown from measurements from space by the IMAGE spacecraft that the dayside hydrogen emission is directly related to dayside reconnection processes. A four channel all-sky images had been operating at South Pole during 2004-2007 to observe auroral features in specific wavelengths channels that allowed a quantitative investigation of proton aurora. This was accomplished by measuring the Hydrogen Balmer beta line at 486.1 nm and by monitoring another wavelength band for subtracting non proton produced background emissions. South Pole allows these measurements because of the 24 hour darkness and favorable conditions even on the dayside. To increase the scientific return it was also attempted to measure the Doppler shift of the hydrogen emissions because that provides diagnostics regarding the energy of the protons. Thus the proton camera measured 3 wavelength bands simultaneously in the vicinity of the Balmer beta line to provide the line intensity near zero Doppler shift, at a substantial Doppler shift and a third channel for background. \n\nThe 4-channel all-sky camera at South Pole was modified in 2008 in order to observe several types of auroras, and to distinguish the cusp reconnection aurora from the normal plasma sheet precipitation. The camera simultaneously operates in four wavelength regions that allow a distinction between auroras that are created by higher energy electrons (greater than 1 keV) and those created by low energy (less than 500 eV) precipitation. The cusp is the location where plasma enters the magnetosphere through the process of magnetic reconnection. This reconnection occurs where the Interplanetary Magnetic Field (IMF) and the terrestrial magnetic field are oriented in opposite directions. \n\nThe data are represented as keograms (geomagnetic north-south slices through the time series of images) for the four different wavelengths. The top of the keogram points to the magnetic south pole. The time series allows a very quick assessment about the presence of aurora, motion, intensity, and brightness differences in the four simultaneously registered channels.", "east": null, "geometry": null, "keywords": "Antarctica; Atmosphere; Aurora; Cosmos; Photo/video; Photo/Video", "locations": "Antarctica", "north": null, "nsf_funding_programs": null, "persons": "Frey, Harald; Mende, Stephen", "project_titles": "Antarctic Auroral Imaging", "projects": [{"proj_uid": "p0000361", "repository": "USAP-DC", "title": "Antarctic Auroral Imaging"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Antarctic Auroral Imaging", "uid": "600070", "west": null}, {"awards": "9316715 Taylor, Susan", "bounds_geometry": ["POINT(0 -90)"], "date_created": "Tue, 01 Jan 2002 00:00:00 GMT", "description": "Micrometeorites dated between 1100 A.D. to 1500 A.D. were collected from the bottom of the South Pole Water Well in December 1995. Element analyses of 181 cosmic glass spherule and micrometeorite samples are in ASCII text and Excel spreadsheet format. Scanning Electron Microscope (SEM) images of the spherules and micrometeorites are in TIFF format. Data are available via ftp.", "east": 0.0, "geometry": ["POINT(0 -90)"], "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Cosmos; Geochemistry; Meteorite; Scanning Electron Microscope (SEM) Images; South Pole", "locations": "South Pole; Antarctica", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Taylor, Susan", "project_titles": "Retrieval and Analysis of Extraterrestrial Particles from the Water Well at the South Pole Station, Antarctica", "projects": [{"proj_uid": "p0000057", "repository": "USAP-DC", "title": "Retrieval and Analysis of Extraterrestrial Particles from the Water Well at the South Pole Station, Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Micrometeorites from the South Pole Water Well", "uid": "609113", "west": 0.0}]

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