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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').
Advanced Search

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"

21106 results found.

  1. LIGO/Virgo S190814bv: GRAWITA TNG NIR imaging of AT2019nqq and AT2019nqc
  2. LIGO/Virgo S190814bv: No strong counterpart candidates in Swift/XRT observations
  3. GRB 190816A: Swift-XRT observations
  4. LIGO/Virgo S190814bv: No candidates from image subtraction in DCT galaxy targeted search
  5. LIGO/Virgo S190814bv: WIRC NIR imaging follow-up of DECam transients
  6. LIGO/Virgo S190814bv: Additional candidates identified in DECam images by the DECam-GROWTH team
  7. LIGO/Virgo S190814bv: Prioritization of Counterpart Candidates based on a Photometric Redshift Analysis by the DECam-GROWTH Team
  8. LIGO/Virgo S190814bv: No candidates found in J-GEM follow-up observations
  9. Fermi trigger No 587775150 Global MASTER-Net observations report
  10. LIGO/Virgo S190814bv : ENGRAVE X-shooter spectra of AT2019nqs and AT2019npy
  11. LIGO/Virgo S190814bv: GRAWITA TNG infrared imaging of desgw-190814e, DG19sevhc and selected galaxies
  12. LIGO/Virgo S190814bv : No Counterpart Candidates in Continued Galaxy Targeted Search with Magellan
  13. LIGO/Virgo S190814bv: No additional candidates from the Zwicky Transient Facility
  14. Baksan Neutrino Observatory Alert 190817.35 Global MASTER-Net observations report
  15. LIGO/Virgo S190814bv: SOAR spectroscopy of 2 DESGW candidates
  16. Baksan Neutrino Observatory Alert 190816.83 Global MASTER-Net observations report
  17. LIGO/Virgo S190814bv: No candidates found in J-GEM follow-up observations
  18. LIGO/Virgo S190814bv: no candidates from optical imaging of selected galaxies at the NOT
  19. LIGO/VIRGO S190814bv: No candidates from ATLAS observations
  20. LIGO/Virgo S190814bv: No candidates from DCT galaxy targeted search and observations of DECam-GROWTH candidates
  21. LIGO/Virgo S190814bv: GROND imaging of candidate galaxies
  22. SUBJECT: LIGO/Virgo S190814bv: GRAWITA VST-ESO PARANAL observations
  23. S190814bv: MASTER analysis of DECam-GROWTH candidates
  24. LIGO/Virgo S190814bv: Konus-Wind observations
  25. LIGO/Virgo S190814bv : No Counterpart Candidates in Galaxy Targeted Search with Magellan
  26. LIGO/Virgo S190814bv: Upper limits from Insight-HXMT/HE observations
  27. LIGO/Virgo S190814bv: Candidates identified in DECam images by the DECam-GROWTH team
  28. LIGO/Virgo S190814bv: GRAWITA TNG infrared imaging of selected galaxies
  29. LIGO/Virgo S190814bv: No Candidates Found in Wide-Field Infrared Search with Palomar Gattini-IR
  30. Fermi trigger No 587505927 Global MASTER-Net observations report
  31. LIGO/VIRGO S190814bv: No candidates from Pan-STARRS and non-detection of AT2019nme
  32. LIGO/Virgo S190814bv Global MASTER-Net observations report
  33. LIGO/Virgo S190814bv: No counterpart candidates in KAIT observations
  34. LIGO/Virgo S190814bv: No Counterparts in DDOTI/OAN Optical Observations
  35. LIGO/Virgo S190814bv: No counterpart candidates in TOROS observations
  36. LIGO/Virgo S190814bv: no counterpart candidates in Nickel/Direct imaging and non-detections of 2019nmd and 2019nme
  37. LIGO/Virgo S190814bv: no counterpart candidates in Keck I MOSFIRE imaging
  38. LIGO/Virgo S190814bv: No candidates from the Zwicky Transient Facility
  39. LIGO/Virgo S190814bv: No counterpart candidates in the Swift/BAT Observations
  40. LIGO/Virgo S190814bv: MeerLICHT coverage second preliminary skymap
  41. LIGO/Virgo S190814bv Global MASTER-Net optical observations
  42. LIGO/Virgo S190814bv : No counterpart candidate in TAROT-GRANDMA observations
  43. LIGO/Virgo S190814bv: no candidates from GOTO imaging observations
  44. LIGO/Virgo S190814bv: Candidates found in initial DESGW search
  45. LIGO/Virgo S190814bv: Upper limits from AGILE-GRID observations
  46. LIGO/Virgo S190814bv: no candidates from WHT imaging of candidate galaxies
  47. LIGO/Virgo S190814bv: GRAWITA TNG imaging of selected galaxies
  48. LIGO/Virgo S190814bv: Coverage and upper limits from MAXI/GSC observations
  49. LIGO/Virgo S190814bv: Liverpool Telescope imaging of selected galaxies
  50. LIGO/Virgo S190814bv: No counterpart candidates in AGILE-MCAL observations
  51. LIGO/Virgo S190814bv: Upper limits from Fermi-GBM Observations
  52. LIGO/Virgo S190814bv: Nordic Optical Telescope imaging of selected galaxies
  53. LIGO/Virgo S190814bv Global MASTER-Net observations report
  54. LIGO/Virgo S190814bv: CLU/NED Galaxies in the 50% Localization Volume
  55. Fermi trigger No 587392154 Global MASTER-Net observations report
  56. IPN triangulation of GRB 190805B
  57. HAWC-190806A: Upper limits from Insight-HXMT/HE observations
  58. FRB 190806: MASTER optical observation
  59. Fermi trigger No 587084236 Global MASTER-Net observations report
  60. HAWC-190806A: Upper limits from Fermi-GBM Observations
  61. HAWC-190806A: Swift-XRT observations
  62. HAWC Burst Alert 1008846_957: Konus-Wind observations
  63. Trigger_11505: Tiled Swift observations
  64. LIGO/Virgo S190808ae: Coverage and upper limits from MAXI/GSC observations
  65. LIGO/Virgo S190808ae: CLU/NED Galaxies in the 50% Localization Volume
  66. LIGO/Virgo S190808ae: No counterpart candidates in HAWC observations
  67. LIGO/Virgo S190808ae Global MASTER-Net observations report
  68. Fermi trigger No 586980202 Global MASTER-Net observations report
  69. Fermi trigger No 586896678 Global MASTER-Net observations report
  70. GRB 190805B: AstroSat CZTI detection
  71. GRB 190804B: Swift-XRT afterglow detection
  72. Alert from the HAWC Burst Monitor
  73. HAWC Alert 190806.56 Global MASTER-Net observations report
  74. Fermi trigger No 586788607 Global MASTER-Net observations report
  75. Fermi trigger No 586800758 Global MASTER-Net observations report
  76. GRB 190805B: Swift-XRT observations
  77. Fermi trigger No 586676451 Global MASTER-Net observations report
  78. GRB 190805B: Tiled Swift observations
  79. GRB 190804B: Swift-XRT observations
  80. Fermi trigger No 586638042 Global MASTER-Net observations report
  81. MAXI GRB190804.33 Global MASTER-Net observations report
  82. Fermi trigger No 586600841 Global MASTER-Net observations report
  83. GRB 190804B: Tiled Swift observations
  84. Fermi trigger No 586574612 Global MASTER-Net observations report
  85. GRB 190731A: Swift/UVOT Upper Limits
  86. GRB 190731A: no OT detected by MASTER
  87. IceCube 190730A: No counterpart candidates or blazar activity in GOTO observations
  88. GRB 190719C: VLT/X-shooter spectroscopic redshift of the host galaxy
  89. GRB 190731A: Swift-XRT afterglow detection
  90. GRB 190731A: Swift ToO observations
  91. Fermi trigger No 586305505 Global MASTER-Net observations report
  92. Fermi trigger No 586305505 Global MASTER-Net observations report
  93. Fermi-LAT Gamma-ray Observations of IceCube-190730A
  94. LIGO/Virgo S190728q: No counterpart candidates in H.E.S.S. observations
  95. LIGO/Virgo S190728q: ZTF Forced Photometry for PS1 and DECam-GROWTH optical candidates, and a note on DECam Photometry from GCN 25215
  96. Fermi trigger No 586240252 Global MASTER-Net observations report
  97. IceCube 190730A: not observable by Fermi-GBM
  98. IceCube-190730A: MASTER optical observation
  99. IceCube-190730A - IceCube observation of a high-energy neutrino candidate event
  100. LIGO/Virgo S190728q: Optical transients from Pan-STARRS coverage during first 2 nights

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