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Start Over Resource Type Archive Capability Type Simple Image Access Protocol
171. Swift UVOT Combined V Intensity Images
ID:
ivo://nasa.heasarc/skyview/swiftuvot
Title:
Swift UVOT Combined V Intensity Images
Short Name:
SWIFTUVOT
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
The Swift UVOT instrument is a 30 cm modified Ritchey-Chretien reflecting telescope launched on board the Swift satellite on November 20, 2004. The range of optical and UV filters can accomodate wavebands between 1700 and 6500 Angstroms. A full field image covers 17x17 arcminutes and at maximum spatial sampling is imaged onto 2048x2048 0.5" pixels. A 1000 second observation can detect point sources to m=22.3 when no filter is used. The Swift Serendipitous Source Catalog (Page et al., 2015) detects sources down to m=23-26 for the six filters in very deep observations, but the typical limits are substantially brighter (~20-23 magnitude). <p> These surveys are mosaics of all Swift UVOT observations released between the start of the mission and July 2017. Data were extracted from the HEASARC archive from the UVOT products directory. Mosaics are provided in six filters and also with no filter, i.e., WHITE. The table below gives the number of observations and bandpasses for each of the filters. For each UVOT observation standard processing generates a counts and exposure file as a single multi-extension FITS file with a separate extension for each filter. To aid processing, these extensions were copied into separate files in directory trees for each filter. Four observations in which the exposure and counts maps did not agree on the filters used were omitted from the processing. <p> Some observations were recorded with 0.5" pixels while others were binned to 1". All 0.5" observations (typically fewer than 10%) were rebinned to the larger pixels for the counts maps since the counts data scales with the pixel size. Since the exposure values are intensive and do not vary significantly based upon the resolution, these data were not generally rebinned unless it was needed to ensure that Order 9 Hips data were produced. <p> The CDS Hipsgen software was used to generate Order 9 HiPS data (~0.8" pixels) for both the Counts and Exposure images. The HiPS (Hierarchical Progressive Survey VO standard) supports multi-resolution mosaics. Any quantitative use of these images should note that the rebinning increases the total counts by a factor of ~(1.0/0.8)^2 ~ 1.56. This software uses a bilinear interpolation to generate HEALPix tiles of an appropriate order (18 in this case). <i>SkyView</i> developed software was used to divide the level 9 counts maps tiles by the corresponding exposure maps to create intensity tiles. Pixels where the exposure was less than 5 seconds were left as NaNs. The lower order (8 to 3) order intensity tiles were then generated by averaging 2x2 sets of the higher order maps treating any missing maps or pixels as NaNs. A HiPS all-sky image was generated by averaged the Order 3 tiles. <p> Only the Intensity HIPS files are presented in the SkyView web page directly, but intensity, counts and exposure maps are available for all seven filters. Note that unlike the XRT HiPS data, the exposure and counts maps have not been clipped. I.e., the source FITS files have been aligned with the coordinate system and thus contain large numbers of unexposed pixels with 0 values. These 0's are simply propogated to HiPS tiles. NaNs are returned in regions which lie outside any of the original source images. For the Intensity map, any pixel for which the exposure was less than 5s is returned as a NaN. <table border> <tr><th align=center>Filter</th><th>Count</th><th>Central Wavelength (&amp;#8491;;)</th><th>Bandpass (&amp;#8491;;)</th><th>Central Frequency(THz)</th><th>Bandpass (THz)</th><th>Coverage</th></tr> <tr><th align=center>WHITE</th><td align='center'>3,000</td><td align='center'>3600</td><td align='center'>1600-6000</td><td align='center'>832</td><td align='center'>500-1874</td> <td>0.0017</td></tr> <tr><th align=center>V</th><td align='center'>30,557</td><td align='center'>5468</td><td align='center'>5083-5852</td>< <td align='center'>548</td><td align='center'>512-590</td> <td>0.0171</td></tr> <tr><th align=center>B</th><td align='center'>28,347</td><td align='center'>4392</td><td align='center'>3904-4880</td> <td align='center'>683</td><td align='center'>614-768</td> <td>0.0112<td></tr> <tr><th align=center>U</th><td align='center'>49,954</td><td align='center'>3465</td><td align='center'>3072-3875</td> <td align='center'>865</td><td align='center'>774-975</td> <td>0.0287</td></tr> <tr><th align=center>UVW1</th><td align='center'>60,690</td><td align='center'>2600</td><td align='center'>2253-2946</td> <td align='center'>1154</td><td align='center'>1017-1330</td><td>0.0277</td></tr> <tr><th align=center>UVM2</th><td align='center'>56,977</td><td align='center'>2246</td><td align='center'>1997-2495</td> <td align='center'>1334</td><td align='center'>1201-1501</td>>td>0.0314</td></tr> <tr><th align=center>UVW2</th><td align='center'>54,590</td><td align='center'>1928</td><td align='center'>1600-2256</td> <td align='center'>1554</td><td align='center'>1328-1874</td><td>0.0260</td></tr> </table> <strong>Observation counts and bandpasses for UVOT Filters</strong> <p> Provenance: Data generated from public images at HEASARC archive. This is a service of NASA HEASARC.
172. Swift UVOT Instrument Log
ID:
ivo://nasa.heasarc/swiftuvlog
Title:
Swift UVOT Instrument Log
Short Name:
SwiftUVOT
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
The UVOT runs only one type of configuration filter/mode/window in a given time interval. This database table, therefore, contains for a given time interval a single record that describes one configuration. This database table is generated by the Swift Data Center. During operation, it is updated on daily basis. This is a service provided by NASA HEASARC .
173. Swift XRT Combined Intensity Images
ID:
ivo://nasa.heasarc/skyview/swiftxrt
Title:
Swift XRT Combined Intensity Images
Short Name:
SWIFTXRT
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
The Swift XRT (<a href="https://ads.harvard.edu/abs/2005SSRv..120..165B">Burrows et al 2005, SSRv, 120, 165</a>) is a sensitive, broad-band (0.2 - 10 keV) X-ray imager with an effective area of about 125 cm**2 at 1.5 keV. The 600 x 600 pixel CCD at the focus provides a 23.6' x 23.6' field of view with a pixel scale of 2.36". The point spread function is 18" (HPD) at 1.5 keV. <p> These XRT surveys represent the data from the first 12.5 years of Swift X-ray observations. They include all data taken in photon counting mode. A total of just over 8% of the sky has some non-zero exposure. The fraction of sky exposed as a function of the exposure is given in the following table: <table border> <tr><th>Exposure</th><td>&gt;0</td> <td>10</td> <td>30</td> <td>100</td> <td>300</td> <td>1000</td> <td>3000</td> <td>1000</td> <td>30000</td> <td>100000</td><td>300000</td></tr> <tr><th>Coverage</th> <td> 8.42 </td><td> 8.37 </td><td> 8.29 </td><td> 7.67 </td><td> 7.29 </td><td> 5.68 </td> <td> 3.40 </td><td> 1.26 </td><td> 0.35 </td><td> 0.044 </td><td> 0.00118</td></th> </table> The individual exposure and counts maps have been combined into a Hierarchical Progressive Survey (HiPS) where the data are stored in tiles in the HEALPix projection at a number of different resulutions. The highest resolution pixels (HEALPix order 17) have a size of roughly 1.6". Data are also stored at lower resolutions at factors of 1/2, 1/4, 1/8, 1/16, and 1/32, and in an all sky image with a resolution 1/256 of the higest resolution. An intensity map has been created as the ratio of the counts and exposure maps. <p> These surveys combine the basic count and exposure maps provided as standard products in the Swift XRT archive in obsid/xrt/products/*xpc_(sk|ex).img.gz. The surveys were created as follows: <ul> <li>All of the exposure maps available in the archive in mid-May 2017 were combined using the CDS-developed Hipsgen tool. This includes 129,063 observations for which both count and exposure files were found in PC mode. Three exposures where there was a counts map but no exposure map were ignored. A few exposure files had more than one exposure extension. 1,082 files had two extensions and 1 file had 3 extensions. The 1084 HDUs in extensions were extracted as separate files and included in the total exposure. The value of 0 was given to the Hipsgen software as the null value for the FITS files. This caused the CDS software to treat such pixels as missing rather than 0 exposure. <li> The counts data was extracted from the counts maps for each observation using <i>SkyView</i> developed software. For any pixel in which a count was recorded, the corresponding exposure file was checked and if there was any exposure (in any of the associated extensions), then the count was retained. If there was no exposure in any of the extensions of the corresponding exposure file, the counts in the pixel were omitted. Once a count was accepted, the overlap between the counts map pixel and the pixels of the corresponding HiPS tile (or tiles) was computed. Each count was then assigned entirely to a single pixel in the HiPS tile randomly but with the destination pixel probabilities weighted by area of the overlap. Thus if several pixels were found in a given counts map pixel they might be assigned to different pixels in the output image. The HiPS pixels (~1.6") used were of substantially higher resolution than the XRT resolution of 18" and somewhat higher than the counts map resolution of 2.36". <p> A total of 183,750,428 photons were extracted from the counts maps while 15,226 were rejected as being from pixels with 0 exposure. There were 501 pixels which required special treatment as straddling the boundaries of the HEALPix projection. <li> The resulting counts tiles were then clipped using the exposure tiles that had been previously generated. Basically this transferred the coverage of the exposure tiles to the counts tiles. Any counts pixel where the corresponding exposure pixel was a NaN was changed to a NaN to indicate that there was no coverage in this region. <p> During the clipping process 137,730 HiPS level 8 were clipped (of 786,432 over the entire sky). There were 12,236 tiles for which there was some exposure but no counts found. During the clipping process 2 photons were found on pixels where there was no corresponding exposure in the exposure tiles. This can happen when the pixel assignment process noted above shifts a photon just outside the exposed region but should be -- as it was -- rare. These photons were deleted. <li> After creating the clipped level 8 counts maps, level 7 to 3 tiles and an all sky map where generated by averaging pixels 2x2 to decrease each level. When adding the four pixels in the level N map together only pixels whose value was not NaN were considered. <li> Finally an intensity map was created by dividing the counts tiles by the exposure tiles. To eliminate gross fluctuations due to rare counts in regions with very low exposure, only regions with exposure > 1 second were retained. A total of 30 photons were deleted due to this criterion. </ul> <p> Note that while any sampler may in principle be used with these data, the Spline sampler may give unexpected results. The spline computation propogates NaNs thought the image and means that even occasional NaNs can corrupt the output image completely. NaNs are very common in this dataset. Also, if the region straddles a boundary in the HEALPix projection, the size of the requested input region is likely to exceed memory limits since the HiPS data are considered a single very large image. Provenance: Data generated from public images at HEASARC archive. This is a service of NASA HEASARC.
174. Swift XRT Instrument Log
ID:
ivo://nasa.heasarc/swiftxrlog
Title:
Swift XRT Instrument Log
Short Name:
SwiftXRT
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
The XRT runs only one type of configuration mode/window in a given time interval. The table therefore contains for a given time interval a single record that describes one configuration. A new record is generated when the following is changing within an observation: new operating mode , new pointing mode, or new window configuration. This database table is generated by the Swift Data Center. During operation, it is updated on daily basis. This is a service provided by NASA HEASARC .
175. Sydney University Molonglo Sky Survey
ID:
ivo://nasa.heasarc/skyview/sumss
Title:
Sydney University Molonglo Sky Survey
Short Name:
SUMSS
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
The Sydney University Molonglo Sky Survey (SUMSS) is a deep radio survey at 843 MHz of the entire sky south of declination -30&amp;#176;;, made using the Molonglo Observatory Synthesis Telescope (<a href="https://www.physics.usyd.edu.au/astrop/most/"> MOST </a>), located near Canberra, Australia. The images from the SUMSS are produced as 4 x 4 degree mosaics of up to seventeen individual observations, to ensure even sensitivity across the sky. The mosaics slightly overlap each other. Data were last updated on January 28, 2015. <p> Images can also be obtained from the <a href="https://www.astrop.physics.usyd.edu.au/cgi-bin/postage.pl">SUMSS Postage Stamp Server</a>. <p> The SUMSS is intended to complement the NRAO-VLA Sky Survey (NVSS) which covered the sky between +90 and -40 deg declination, at a frequency of 1400MHz. <p> Provenance: The SUMSS project team, University of Sydney. This is a service of NASA HEASARC.
176. The Extended IRAS Galaxy Atlas
ID:
ivo://irsa.ipac/IRAS/Images/EIGA
Title:
The Extended IRAS Galaxy Atlas
Short Name:
EIGA
Date:
31 Mar 2023 23:00:00
Publisher:
NASA/IPAC Infrared Science Archive
Description:
The Extended IRAS Galaxy Atlas (EIGA) is an extension of the original IRAS Galaxy Atlas (IGA) to b = 6.7 deg.. High resolution images at 60 microns and 100 microns have been produced to match the latitude coverage of radio continuum observations obtained as part of the Canadian Galactic Plane Survey (CGPS). Also associated with the EIGA and IGA is the Mid-Infrared Galaxy Atlas (MIGA).
177. The Galactic Census of High and Medium-mass Protostars
ID:
ivo://irsa.ipac/CHaMP/Images
Title:
The Galactic Census of High and Medium-mass Protostars
Short Name:
CHaMP
Date:
01 May 2023 19:01:00
Publisher:
NASA/IPAC Infrared Science Archive
Description:
CHaMP is a multi-faceted survey of molecular clouds and star formation along the Carina Arm of the Milky Way (300d > l > 280d, -4d < b < +2d).
178. The Hawaii Hubble Deep Field North: Band B
ID:
ivo://nasa.heasarc/skyview/hawaii-hdf-b
Title:
The Hawaii Hubble Deep Field North: Band B
Short Name:
Hawaii HDF B
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
The Hawaii-HDF-N is an intensive multi-color imaging survey of 0.2 sq. degrees centered on the HDF-N. Data were collected on the NOAO 4m Mayall telescope, the National Astronomical Observatory of Japan 8.2m Subaru telescope and the University of Hawaii 2.2m telescope. Deep U, B, V, R, I, and z' data were obtained over the whole field and deep HK' data over the Chandra Deep Field North. Details are available in the references. [Adapted from reference website.] <P> Two different images are given in the V band (V0201 and V0401) from observations separated by about a month that had substantial differences in seeing. Provenance: Data downloaded from the reference website. A formatting error in the FITS files was corrected.. This is a service of NASA HEASARC.
179. The HI 4-PI Survey
ID:
ivo://nasa.heasarc/skyview/hi4pi
Title:
The HI 4-PI Survey
Short Name:
HI4PI
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
The HI 4-PI Survey (HI4PI) is a 21-cm all-sky survey of neutral atomic hydrogen. It is constructed from the Effelsberg-Bonn HI Survey (EBHIS), made with the 100-m radio telescope at Effelsberg/Germany, and the Galactic All-Sky Survey (GASS), observed with the Parkes 64-m dish in Australia. HI4PI comprises HI line emission from the Milky Way. This dataset is the atomic neutral hydrogen (HI) column density map derived from HI4PI (|Vlsr| < 600 km/s). Provenance: Argelander-Institut für Astronomie (AIfA), Max-Planck-Institut für Radioastronomie (MPIfR), and CSIRO/Australia; data provided by B. Winkel. This is a service of NASA HEASARC.
180. The Infrared Telescope in Space Data Atlas
ID:
ivo://irsa.ipac/IRTS/Images
Title:
The Infrared Telescope in Space Data Atlas
Short Name:
IRTS
Date:
27 Sep 2024 01:00:00
Publisher:
NASA/IPAC Infrared Science Archive
Description:
The Infrared Telescope in Space (IRTS) is a cryogenically cooled, small infrared telescope that flew from March - April in 1995. It surveyed approximately 10% of the sky with a relatively wide beam during its 20 day mission. Four focal-plane instruments , the Near-Infrared Spectrometer (NIRS), the Mid-Infrared Spectrometer (MIRS), the Far-Infrared Line Mapper (FILM), and the Far-Infrared Photometer (FIRP) made simultaneous observations of the sky at wavelengths ranging from 1 to 1000 um.