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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

4059 results found.

  1. LIGO/Virgo S190828l: Upper limits from AGILE-GRID observations
  2. LIGO/Virgo S190828l: Upper limits from IceCube neutrino searches
  3. LIGO/Virgo S190828j: Upper limits from IceCube neutrino searches
  4. LIGO/Virgo S190828l Global MASTER-Net observations report
  5. LIGO/Virgo S190828l: Coverage and upper limits from MAXI/GSC observations
  6. LIGO/Virgo S190828l: No counterpart candidates in AGILE-MCAL observations
  7. LIGO/Virgo S190828j: Coverage and upper limits from MAXI/GSC observations
  8. LIGO/Virgo S190828j : no neutrino counterpart candidate in ANTARES search
  9. LIGO/Virgo S190828l : no neutrino counterpart candidate in ANTARES search
  10. LIGO/Virgo S190828j: Upper limits from AGILE-GRID observations
  11. LIGO/Virgo S190828l: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  12. LIGO/Virgo S190828j: Updated Sky Localization
  13. LIGO/Virgo S190828l: Identification of a GW compact binary merger candidate
  14. LIGO/Virgo S190828l: No counterpart candidates in HAWC observations
  15. LIGO/Virgo S190828j: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  16. LIGO/Virgo S190828j: No counterpart candidates in HAWC observations
  17. LIGO/Virgo S190828j: No counterpart candidates in AGILE-MCAL observations
  18. LIGO/Virgo S190828j: Identification of a GW compact binary merger candidate
  19. LIGO/Virgo S190814bv: Correction of ASKAP coordinates
  20. LIGO/Virgo S190814bv: DESGW non-detection of AT2019osy/ASKAP 005547-270433
  21. LIGO/Virgo S190814bv: Palomar 200-in spectroscopic redshift and host galaxy properties of ASKAP source AT2019osy
  22. LIGO/Virgo S190814bv: Optical non-detection of radio source AT2019osy from CFHT
  23. LIGO/Virgo S190814bv: DECam-GROWTH detection of an optical counterpart to the radio source AT2019osy
  24. LIGO/Virgo S190814bv: Detection of a candidate radio counterpart with ASKAP
  25. LIGO/Virgo S190814bv: Final list of candidates from the DESGW coadd analysis from the week long search campaign
  26. LIGO/Virgo S190814bv: CFHTphotometryof AT2019npv
  27. LIGO/Virgo S190814bv: SOAR spectroscopy of DECam candidates AT2019npw and AT2019num
  28. LIGO/Virgo S190814bv : Magellan IMACS Spectrum of AT2019npv classified as a Type Ib supernova
  29. LIGO/Virgo S190814bv: SALT optical spectrum of candidate DG19aqbkc
  30. LIGO/Virgo S190814bv: Radio non-detection of DG19wxnjc/AT2019npv with the VLA
  31. LIGO/Virgo S190814bv: Keck II NIRES classification of DG19wxnjc/AT2019npv as a stripped envelope supernova
  32. LIGO/Virgo S190814bv: LCO Photometry of DG19wxnjc/AT2019npv
  33. LIGO/Virgo S190814bv: MASTER prediscovery and postdiscovery observations DECam candidate DG19wxnjc/AT2019npv field
  34. LIGO/Virgo S190814bv: No radio counterpart to DG19wxnjc/AT2019npv in ASKAP observations
  35. LIGO/Virgo S190814bv: Archival detection of DG19wxnjc/AT2019npv in DES data
  36. Fermi GBM-190816: Updated localization of subthreshold GRB-GW candidate
  37. LIGO/Virgo S190814bv: Keck NIRES spectroscopy of DG19wxnjc/AT2019npv
  38. LIGO/Virgo S190814bv: Photometric Evolution of DECAM candidates
  39. LIGO/Virgo S190814bv: DESGW photometry of AT2019npv
  40. LIGO/Virgo S190814bv: GROND follow-up observations of AT2019npv
  41. LIGO/Virgo S190814bv: Further Pan-STARRS z-band observations and AT2019npv photometry
  42. LIGO/Virgo S190814bv: WHT spectroscopy of the host of AT2019npv
  43. LIGO/Virgo S190814bv: NIR imaging follow-up of ASKAP transient
  44. LIGO/Virgo S190814bv: ENGRAVE VLT/HAWK-I observations and archival detection of the CFHT candidate
  45. Fermi GBM-190816: MASTER-Net optical observation report
  46. LIGO/Virgo S190814bv: No radio counterpart detected in ASKAP observations
  47. LIGO/Virgo S190814bv: a potential faint optical counterpart in CFHT imaging
  48. LIGO/Virgo S190822c: Retraction of GW compact binary merger candidate
  49. LIGO/Virgo S190822c: CLU/NED Galaxies in the 50% Localization Volume
  50. LIGO/Virgo S190822c Global MASTER-Net observations report
  51. LIGO/Virgo S190822c: Upper limits from IceCube neutrino searches
  52. LIGO/Virgo S190814bv: new candidate from DESGW
  53. LIGO/Virgo S190814bv: No Optical Counterpart Candidates in Second-Epoch Lick/KAIT Observations
  54. Fermi GBM-190816: No counterpart candidates in Fermi-LAT observations
  55. LIGO/Virgo S190814bv: further candidates from DESGW
  56. LIGO/Virgo S190814bv: SOAR spectroscopy of AT2019noq and AT2019ntn
  57. LIGO/Virgo S190814bv: No Counterpart Candidates in Las Cumbres Observatory Galaxy Targeted Search
  58. LIGO/Virgo S190814bv: AT2019nqq 10.4m GTC spectroscopy
  59. LIGO/Virgo S190814bv: Further Pan-STARRS observations and transient sources
  60. LIGO/Virgo S190814bv: RATIR Optical observations of DECam transients
  61. LIGO/Virgo GBM-190816: no counterpart candidates in the Swift/BAT Observations
  62. LIGO/Virgo S190814bv: No neutrino candidates at Pierre Auger Observatory
  63. Fermi GBM-190816+LIGO/Virgo : no neutrino counterpart candidate in ANTARES search
  64. Fermi GBM-190816: A subthreshold GRB candidate potentially associated with a subthreshold LIGO/Virgo compact binary merger candidate
  65. LIGO/Virgo S190814bv: GRAWITA TNG NIR imaging of AT2019nqq and AT2019nqc
  66. LIGO/Virgo S190814bv: No strong counterpart candidates in Swift/XRT observations
  67. LIGO/Virgo S190814bv: DESGW candidate update
  68. LIGO/Virgo S190814bv: No candidates from image subtraction in DCT galaxy targeted search
  69. LIGO/Virgo S190814bv: WIRC NIR imaging follow-up of DECam transients
  70. LIGO/Virgo S190814bv: Keck/MOSFIRE NIR spectroscopy of DG19njmjc (= AT 2019nra)
  71. LIGO/Virgo S190814bv: DG19dnjlc is not offset from its host galaxy
  72. LIGO/Virgo S190814bv: Additional candidates identified in DECam images by the DECam-GROWTH team
  73. LIGO/VIRGO S190814bv: AbAO non-detection of AT2019nme
  74. LIGO/Virgo S190814bv: Prioritization of Counterpart Candidates based on a Photometric Redshift Analysis by the DECam-GROWTH Team
  75. LIGO/Virgo S190814bv: Not observable by CALET
  76. LIGO/Virgo S190814bv: No candidates found in J-GEM follow-up observations
  77. LIGO/Virgo S190814bv: Pan-STARRS imaging indicates DG19sevhc (AT2019npy) is a proper motion star
  78. LIGO/Virgo S190814bv: Fermi-LAT search for a high-energy gamma-ray counterpart
  79. LIGO/Virgo S190814bv : ENGRAVE X-shooter spectra of AT2019nqs and AT2019npy
  80. LIGO/Virgo S190814bv: GRAWITA TNG infrared imaging of desgw-190814e, DG19sevhc and selected galaxies
  81. LIGO/Virgo S190814bv : No Counterpart Candidates in Continued Galaxy Targeted Search with Magellan
  82. LIGO/Virgo S190814bv: No additional candidates from the Zwicky Transient Facility
  83. LIGO/Virgo S190814bv: SOAR spectroscopy of 2 DESGW candidates
  84. LIGO/Virgo S190814bv: No candidates found in J-GEM follow-up observations
  85. LIGO/Virgo S190814bv: no candidates from optical imaging of selected galaxies at the NOT
  86. LIGO/VIRGO S190814bv: No candidates from ATLAS observations
  87. LIGO/Virgo S190814bv: No candidates from DCT galaxy targeted search and observations of DECam-GROWTH candidates
  88. LIGO/Virgo S190814bv: New candidates from DECam DESGW difference imaging search
  89. LIGO/Virgo S190814bv: GROND imaging of candidate galaxies
  90. SUBJECT: LIGO/Virgo S190814bv: GRAWITA VST-ESO PARANAL observations
  91. LIGO/Virgo S190814bv: Konus-Wind observations
  92. LIGO/Virgo S190816i: Retraction of GW compact binary merger candidate
  93. LIGO/Virgo S190814bv : No Counterpart Candidates in Galaxy Targeted Search with Magellan
  94. LIGO/Virgo S190814bv: Upper limits from Insight-HXMT/HE observations
  95. LIGO/Virgo S190814bv: Candidates identified in DECam images by the DECam-GROWTH team
  96. LIGO/Virgo S190814bv: GRAWITA TNG infrared imaging of selected galaxies
  97. LIGO/Virgo S190814bv: No candidates identified in DECam data by visual inspection
  98. LIGO/Virgo S190814bv: No Counterpart Candidates in Las Cumbres Observatory Galaxy Targeted Search
  99. LIGO/Virgo S190814bv: No Candidates Found in Wide-Field Infrared Search with Palomar Gattini-IR
  100. LIGO/VIRGO S190814bv: No candidates from Pan-STARRS and non-detection of AT2019nme

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