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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"
  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: DESGW candidate update
  5. LIGO/Virgo S190814bv: No candidates from image subtraction in DCT galaxy targeted search
  6. LIGO/Virgo S190814bv: WIRC NIR imaging follow-up of DECam transients
  7. LIGO/Virgo S190814bv: Keck/MOSFIRE NIR spectroscopy of DG19njmjc (= AT 2019nra)
  8. LIGO/Virgo S190814bv: DG19dnjlc is not offset from its host galaxy
  9. LIGO/Virgo S190814bv: Additional candidates identified in DECam images by the DECam-GROWTH team
  10. LIGO/VIRGO S190814bv: AbAO non-detection of AT2019nme
  11. LIGO/Virgo S190814bv: Prioritization of Counterpart Candidates based on a Photometric Redshift Analysis by the DECam-GROWTH Team
  12. LIGO/Virgo S190814bv: Not observable by CALET
  13. LIGO/Virgo S190814bv: No candidates found in J-GEM follow-up observations
  14. Fermi trigger No 587775150 Global MASTER-Net observations report
  15. GRB 190817A: Fermi GBM Final Real-time Localization
  16. LIGO/Virgo S190814bv: Pan-STARRS imaging indicates DG19sevhc (AT2019npy) is a proper motion star
  17. LIGO/Virgo S190814bv: Fermi-LAT search for a high-energy gamma-ray counterpart
  18. LIGO/Virgo S190814bv : ENGRAVE X-shooter spectra of AT2019nqs and AT2019npy
  19. LIGO/Virgo S190814bv: GRAWITA TNG infrared imaging of desgw-190814e, DG19sevhc and selected galaxies
  20. LIGO/Virgo S190814bv : No Counterpart Candidates in Continued Galaxy Targeted Search with Magellan
  21. LIGO/Virgo S190814bv: No additional candidates from the Zwicky Transient Facility
  22. Baksan Neutrino Observatory Alert 190817.35 Global MASTER-Net observations report
  23. LIGO/Virgo S190814bv: SOAR spectroscopy of 2 DESGW candidates
  24. Baksan Neutrino Observatory Alert 190816.83 Global MASTER-Net observations report
  25. LIGO/Virgo S190814bv: No candidates found in J-GEM follow-up observations
  26. LIGO/Virgo S190814bv: no candidates from optical imaging of selected galaxies at the NOT
  27. LIGO/VIRGO S190814bv: No candidates from ATLAS observations
  28. LIGO/Virgo S190814bv: No candidates from DCT galaxy targeted search and observations of DECam-GROWTH candidates
  29. LIGO/Virgo S190814bv: New candidates from DECam DESGW difference imaging search
  30. LIGO/Virgo S190814bv: GROND imaging of candidate galaxies
  31. SUBJECT: LIGO/Virgo S190814bv: GRAWITA VST-ESO PARANAL observations
  32. S190814bv: MASTER analysis of DECam-GROWTH candidates
  33. LIGO/Virgo S190814bv: Konus-Wind observations
  34. GRB 190816A: Swift detection of a burst
  35. LIGO/Virgo S190816i: Retraction of GW compact binary merger candidate
  36. LIGO/Virgo S190814bv : No Counterpart Candidates in Galaxy Targeted Search with Magellan
  37. LIGO/Virgo S190814bv: Upper limits from Insight-HXMT/HE observations
  38. GRB 190813A: Insight-HXMT/HE detection
  39. GRB 190814A: Insight-HXMT/HE detection
  40. LIGO/Virgo S190814bv: Candidates identified in DECam images by the DECam-GROWTH team
  41. LIGO/Virgo S190814bv: GRAWITA TNG infrared imaging of selected galaxies
  42. LIGO/Virgo S190814bv: No candidates identified in DECam data by visual inspection
  43. LIGO/Virgo S190814bv: No Counterpart Candidates in Las Cumbres Observatory Galaxy Targeted Search
  44. LIGO/Virgo S190814bv: No Candidates Found in Wide-Field Infrared Search with Palomar Gattini-IR
  45. Fermi trigger No 587505927 Global MASTER-Net observations report
  46. LIGO/VIRGO S190814bv: No candidates from Pan-STARRS and non-detection of AT2019nme
  47. LIGO/Virgo S190814bv: des-gw190814b is a moving object
  48. LIGO/Virgo S190814bv Global MASTER-Net observations report
  49. LIGO/Virgo S190814bv: No counterpart candidates in KAIT observations
  50. LIGO/Virgo S190814bv: No Counterparts in DDOTI/OAN Optical Observations
  51. LIGO/Virgo S190814bv: no counterpart candidates in Thacher imaging
  52. LIGO/Virgo S190814bv: no counterpart candidates in Swope imaging
  53. LIGO/Virgo S190814bv: No counterpart candidates in TOROS observations
  54. LIGO/Virgo S190814bv: des-gw190814a is consistent with an asteroid
  55. LIGO/Virgo S190814bv: no counterpart candidates in Nickel/Direct imaging and non-detections of 2019nmd and 2019nme
  56. LIGO/Virgo S190814bv: ATLAS forced photometry non-detections of DESGW candidates
  57. Non-detection of DESGW-190814a in ZTF forced photometry
  58. LIGO/Virgo S190814bv: no counterpart candidates in Keck I MOSFIRE imaging
  59. LIGO/Virgo S190814bv: No candidates from the Zwicky Transient Facility
  60. LIGO/Virgo S190814bv: KMTNet observation
  61. LIGO/Virgo S190814bv: No counterpart candidates in the Swift/BAT Observations
  62. LIGO/Virgo S190814bv: MeerLICHT coverage second preliminary skymap
  63. LIGO/Virgo S190814bv Global MASTER-Net optical observations
  64. LIGO/Virgo S190814bv : No counterpart candidate in TAROT-GRANDMA observations
  65. LIGO/Virgo S190814bv: no candidates from GOTO imaging observations
  66. LIGO/Virgo S190814bv: Candidates found in initial DESGW search
  67. LIGO/Virgo S190814bv: Upper limits from AGILE-GRID observations
  68. IPN triangulation of GRB 190813A (short)
  69. LIGO/Virgo S190814bv: Update on Sky-Localization and Source-Classification
  70. LIGO/Virgo S190814bv: no candidates from WHT imaging of candidate galaxies
  71. LIGO/Virgo S190814bv: GRAWITA TNG imaging of selected galaxies
  72. LIGO/Virgo S190814bv : no neutrino counterpart candidate in ANTARES search
  73. LIGO/Virgo S190814bv: Coverage and upper limits from MAXI/GSC observations
  74. LIGO/Virgo S190814bv: Liverpool Telescope imaging of selected galaxies
  75. LIGO/Virgo S190814bv: No counterpart candidates in AGILE-MCAL observations
  76. LIGO/Virgo S190814bv: Upper limits from Fermi-GBM Observations
  77. LIGO/Virgo S190814bv: Nordic Optical Telescope imaging of selected galaxies
  78. LIGO/Virgo S190814bv: Identification of a GW compact binary merger candidate
  79. LIGO/Virgo S190814bv: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  80. LIGO/Virgo S190814bv Global MASTER-Net observations report
  81. LIGO/Virgo S190814bv: Upper limits from IceCube neutrino searches
  82. LIGO/Virgo S190814bv: CLU/NED Galaxies in the 50% Localization Volume
  83. GRB 190814A: Fermi GBM Final Real-time Localization
  84. Fermi trigger No 587392154 Global MASTER-Net observations report
  85. GRB 190813A: Fermi GBM Final Real-time Localization
  86. IPN triangulation of GRB 190805B
  87. HAWC-190806A: Upper limits from Insight-HXMT/HE observations
  88. FRB 190806: MASTER optical observation
  89. Konus-Wind observation of GRB 190810A
  90. IPN triangulation of GRB 190810A (short)
  91. Fermi trigger No 587084236 Global MASTER-Net observations report
  92. GRB 190810A: Fermi GBM Final Real-time Localization
  93. HAWC-190806A: upper limits from INTEGRAL SPI-ACS and IBIS prompt observation
  94. HAWC-190806A: Upper limits from Fermi-GBM Observations
  95. HAWC-190806A: Swift-XRT observations
  96. HAWC Burst Alert 1008846_957: Konus-Wind observations
  97. GRB 190726A: Insight-HXMT/HE detection
  98. Correction to Swift GCN 25303
  99. Trigger_11505: Tiled Swift observations
  100. LIGO/Virgo S190728q: New optical candidates from the DESGW program

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