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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"

37788 results found.

  1. GRB 190604B: Kitab observatory optical upper limit
  2. GRB 190604A: AstroSat CZTI detection
  3. GRB 190604B: Swift-BAT refined analysis
  4. GRB 190530A: optical follow-up observations at Konkoly
  5. GRB 190604B: BOOTES-3 early optical limits
  6. GRB 190604B: Swift-XRT refined Analysis
  7. GRB190604B: Swift/UVOT detection
  8. GRB 190604B: Enhanced Swift-XRT position
  9. GRB190530A: Photometric follow-up with GROWTH-India telescope
  10. GRB 190604B: Prompt enhanced Swift-XRT position
  11. GRB 190604B: Swift detection of a burst
  12. Fermi trigger No 581337762 Global MASTER-Net observations report
  13. GRB190604A: BALROG localization (Fermi Trigger 581337762 / GRB 190604446)
  14. GRB 190604A: Fermi GBM Final Real-time Localization
  15. GRB 190531B: CALET Gamma-Ray Burst Monitor detection
  16. LIGO/Virgo S190602aq: Upper limits from Insight-HXMT/HE observations
  17. Fermi trigger No 581281470 Global MASTER-Net observations report
  18. GRB 190603A: Fermi GBM Final Real-time Localization
  19. GRB 190531B: Swift/UVOT Upper Limits
  20. Konus-Wind observation of GRB 190531B
  21. GRB 190530A: R-band observation from HCT
  22. LIGO/Virgo S190602aq: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  23. LIGO/Virgo S190602aq: upper limit in INTEGRAL SPI-ACS prompt observations
  24. LIGO/Virgo S190602aq: No counterpart candidates in Fermi-LAT observations
  25. LIGO/Virgo S190602aq: No counterpart candidates in the Swift/BAT Observations
  26. LIGO/Virgo S190602aq: Upper limits from Fermi-GBM Observations
  27. Konus-Wind observation of extremely bright GRB 190530A
  28. GRB 190530A: Insight-HXMT/HE detection
  29. GRB 190531B: Insight-HXMT/HE detection
  30. GRB 190530A: Mondy and AbAO optical observations
  31. GRB 190531B: VLT optical upper limit
  32. Fermi trigger No 581068049 Global MASTER-Net observations report
  33. GRB 190530A: Konkoly optical observations of the afterglow
  34. GRB 190530A: SAO RAS optical observations
  35. GRB 190531B: MASTER optical observation
  36. GRB 190531B: Swift-XRT afterglow detection
  37. GRB 190531B: Fermi GBM observations
  38. Fermi Fermi trigger No 581002688 Global MASTER-Net observations report
  39. GRB 190530A: Swift/UVOT Detection
  40. GRB 190531B: Swift ToO observations
  41. GRB 190531B: Fermi-LAT detection
  42. GRB 190530A: Steep afterglow decay found by OSN
  43. GRB 190531B: name correction re. GCN 24696
  44. GRB 190530A: AbAO optical observations
  45. GRB 190530A: Xinglong 2.16m optical observation
  46. Fermi Trigger 581026217 / GRB 190531840 / GRB190531A: BALROG localization
  47. GRB 190531B: Fermi GBM Final Real-time Localization
  48. GRB 190530A: AstroSat CZTI detection
  49. GRB 190530A: optical afterglow detection by 5 MASTER telescopes
  50. GRB 190530A: Fermi GBM observation
  51. GRB 190531A: Fermi GBM Final Real-time Localization
  52. GRB 190530A: COATLI Optical Detection of the Fading Afterglow
  53. GRB 190530A: Swift-XRT afterglow detection
  54. GRB 190530A: GWAC-F30 optical detection
  55. GRB 190530A: OAJ optical detection
  56. GRB 190530A: NOT photometry and spectroscopy
  57. Fermi GRB190530.43 Global MASTER-Net observations report
  58. GRB 190530A: Bright afterglow confirmed by OSN
  59. GRB 190530A: AGILE/GRID analysis
  60. GRB 190530A: Swift ToO observations
  61. GRB 190530A: MASTER OT detection
  62. GRB 190530A: Fermi-LAT detection
  63. GRB 190530A: AGILE-MCAL detection
  64. Fermi Trigger 580904353 / GRB 190530430 / GRB190530A: BALROG localization
  65. GRB 190530A: Fermi GBM Final Real-time Localization
  66. GRB 190525A: AstroSat CZTI detection
  67. GRB 190525A: Insight-HXMT/HE detection
  68. Fermi GRB190525.67 Global MASTER-Net observations report
  69. Fermi GRB190525.03 Global MASTER-Net observations report
  70. GRB 190525A: Fermi GBM Final Real-time Localization
  71. Konus-Wind observation of GRB 190519A
  72. LIGO/Virgo S190521g: Upper limits from Insight-HXMT/HE observations
  73. LIGO/Virgo S190521r: RATIR Optical and NIR Observations of the CNEOST Transient
  74. LIGO/Virgo S190521g: Swift/BAT Counterpart Search
  75. LIGO/Virgo S190521r: Swift/BAT Counterpart Search
  76. LIGO/Virgo S190521r: Coverage and upper limits from Fermi-LAT observations
  77. LIGO/Virgo S190521r: Upper limits from Fermi-GBM observations
  78. LIGO/Virgo S190521g : Upper limits from Fermi-GBM observations
  79. LIGO/Virgo S190521g: No candidate counterpart in Fermi-LAT observations
  80. LIGO/Virgo S190521r: No counterpart candidates in INTEGRAL SPI/ACS prompt observation
  81. LIGO/Virgo S190519bj: Fermi-LAT search for a high-energy gamma-ray counterpart
  82. LIGO/Virgo S190521g: No counterpart candidates in INTEGRAL SPI/ACS & IBIS/PICsIT prompt observations
  83. LIGO/Virgo S190521g: INTEGRAL SPI/ACS prompt observation
  84. LIGO/Virgo S190519bj: Upper limits from Insight-HXMT/HE observations
  85. Fermi GRB190520.6 Global MASTER-Net observations report
  86. GRB 190519A: AstroSat CZTI detection
  87. GRB 190519A: Swift/UVOT Upper Limits
  88. GRB 190519A: CALET Gamma-Ray Burst Monitor detection
  89. LIGO/Virgo S190519bj: Swift/BAT Counterpart Search
  90. GRB 190519A: Swift-XRT refined Analysis
  91. GRB 190519A: Swift-BAT refined analysis
  92. LIGO/Virgo S190519bj: Fermi GBM Observations
  93. LIGO/Virgo S190519bj: INTEGRAL SPI/ACS prompt observation
  94. GRB 190519A: Enhanced Swift-XRT position
  95. GRB 190519A: Fermi GBM observation
  96. GRB 190519A: Swift detection of a burst
  97. GRB 190519A: Fermi GBM Final Real-time Localization
  98. LIGO/Virgo S190517h: INTEGRAL prompt observation
  99. Fermi GRB190517.81 Global MASTER-Net observations report
  100. GRB 190511A: Swift/UVOT further analysis

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