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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"

32692 results found.

  1. GRB 251017A: COLIBRÍ Early Afterglow Detection
  2. GRB 251016B: AstroSat CZTI detection
  3. GRB 251017A: BOOTES-5/JGT early optical afterglow detection
  4. GRB 251016A: CALET Gamma-Ray Burst Monitor detection
  5. GRB 251016B: CALET Gamma-Ray Burst Monitor detection
  6. GRB 251013C: JinShan observations of the non-thermal rebrightening of the optical counterpart
  7. GRB 251013C: SVOM/COLIBRÍ (FM-GFT) observations of a strong and late rebrightening of the optical counterpart
  8. GRB 251007B: Swift-BAT refined analysis
  9. GRB 251014D: Swift-BAT refined analysis
  10. GRB 251016A: BOOTES-6/DPRT optical upper limit
  11. GRB 251016A: Glowbug gamma-ray detection of a short burst
  12. GRB 251013C: VLA detection
  13. Fermi GRB 251016A: Global MASTER-Net observations report
  14. LIGO/Virgo/KAGRA S251014cn: Updated Sky localization
  15. GRB 251014B: PRIME J-band upper limit
  16. Upper limits from a search for additional neutrino events in IceCube
  17. GRB 251013C: Kilonova-Catcher optical afterglow detection
  18. Fermi-LAT Gamma-ray Observations of IceCube-251014A
  19. GRB 251013D: Swift/UVOT Observations
  20. GRB 251013C: Swift/UVOT Detection
  21. Konus-Wind detection of GRB 251007A
  22. GRB 251013C, GCN Circular 42267, errata corrige
  23. GRB 251013C: detection of a radio counterpart at 15.5GHz
  24. GRB 251013C: SVOM/ECLAIRs refined analysis
  25. GRB 251014B: Swift/UVOT Upper Limits
  26. GRB 251014B: VLT/FORS2 Optical Observation
  27. GRB 251014D: Swift/UVOT Upper Limits
  28. GRB 251013C: MAO/AZT-22 optical observations
  29. GRB 251011B: SVOM/VT optical upper limit
  30. GRB 251013D: Fermi GBM Observation
  31. GRB 251013C: SVOM/COLIBRÍ (FM-GFT) further multi-band optical observations
  32. GRB 251014A: Swift-BAT refined analysis
  33. GRB 251013C: OHP/T193 further optical observations and possible color evolution
  34. GRB 251013C: Calapai Observatory, Massa S. Giorgio (Messina), optical observation
  35. GRB 251014A: PRIME near-infrared upper limits
  36. GRB 251014A: Glowbug gamma-ray detection of a likely short burst
  37. GRB 251014A: VLT/FORS2 Optical Observation
  38. GRB 251013C: Osservatorio Astronomico "Nastro Verde" optical observations: detection of an bright optical counterpart
  39. GRB 251012A: Glowbug gamma-ray detection of a likely short burst
  40. GRB 251013C: MarSEC, optical afterglow photometry
  41. GRB 251013C: OHP/T193 optical afterglow photometry and spectroscopy
  42. GRB 251014B: Swift ToO observations
  43. GRB 251013D: LAST optical upper limit on Swift/BAT-GUANO localization
  44. GRB 251014B: Swift/BAT-GUANO arcminute localization of a short burst
  45. GRB 251013C: Bassano Bresciano Observatory optical observations
  46. GRB 251013C: Early and late-time optical counterpart detection by LCO
  47. GRB 251013C: Fermi GBM Observation
  48. GRB 251013D: Swift ToO observations
  49. GRB 251014A: DDOTI Upper Limit
  50. GRB 251013C NUTTelA-TAO / BSTI Early Measurements
  51. LIGO/Virgo/KAGRA S251014cn: Identification of a GW compact binary merger candidate
  52. GRB 251013C: ULL-ASTRO-MASTER detection of the optical afterglow with the LCO 40-cm telescope at Sutherland Observatory
  53. GRB 251013C: Asiago optical observations
  54. GRB 251013A: CALET Gamma-Ray Burst Monitor detection
  55. GRB 251013C: ABObservatory optical observations
  56. GRB 251014A: SAO RAS optical upper limit
  57. GRB 251014A: Fermi GBM Observation
  58. GRB 251013C: J band observations by SYSU 80cm infrared telescope
  59. GRB 251013C: EP-FXT counterpart detection
  60. GRB 251013C: AstroSat CZTI detection
  61. GRB 251011A: Swift/BAT-GUANO arcminute localization of a burst
  62. GRB 251013D: Swift/BAT-GUANO arcminute localization of a burst
  63. GRB 251013C: ALMA detection
  64. GRB 251013C: SVOM/COLIBRÍ (FM-GFT) detection of the optical counterpart
  65. GRB 251013C: DDOTI detection of the optical afterglow
  66. GRB 251013C: SLKT optical afterglow photometry
  67. Swift GRB 251014A: Global MASTER-Net observations report
  68. Fermi GRB 251013C: Global MASTER-Net observations report
  69. Fermi GRB 251013B: Global MASTER-Net observations report
  70. Fermi GRB 251013D: Global MASTER-Net observations report
  71. GRB 251013C: Swift-XRT counterpart detection
  72. GRB 251013C: GOTO optical afterglow detection
  73. GRB 251013C: SAO RAS optical observations
  74. GRB 251013C: LCO optical afterglow detection
  75. GRB 251013C: Optical Observations via Virtual Telescope Project, Italy
  76. GRB 251013C: NOT spectroscopic redshift z = 0.572
  77. GRB 251013C: LAST detection of optical counterpart
  78. GRB 251013C: BOOTES-6 early optical detection
  79. GRB 251013C: SVOM/VT optical observation
  80. GRB 251013C: SVOM detection of a burst
  81. LIGO/Virgo/KAGRA S251013x: Updated Sky localization and Source Classification
  82. GRB 251013B: SVOM/GRM observation
  83. GRB 251013A: SVOM/GRM observation
  84. GRB 251003A: Mondy optical upper limit
  85. MASTER OT J011025.98-583210.6 : SVOM/VT optical observation
  86. Fermi GRB 251013A: Global MASTER-Net observations report
  87. LIGO/Virgo/KAGRA S251013x: Identification of a GW compact binary merger candidate
  88. GRB 251011B inspection: MASTER orphan GRB detection
  89. GRB 251011A: Insight-HXMT detection
  90. GRB 251011B: Swift/UVOT Upper Limits
  91. Fermi GRB 251011A: Global MASTER-Net observations report
  92. GRB 251011B: SVOM/GRM observation
  93. GRB 251011B: Fermi GBM Observation
  94. GRB 251011B : MASTER optical observations
  95. GRB 251010A: AstroSat CZTI detection
  96. GRB 251011A: AstroSat CZTI detection
  97. GRB 251009B: SVOM/GRM observation of short GRB
  98. GRB 251007B: Swift/UVOT Upper Limits
  99. GRB251007A: Swift/UVOT Detection
  100. GRB 251009A: GECAM-B detection of a short burst

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