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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"

32711 results found.

  1. LIGO/Virgo/KAGRA S241109bn: ATLAS observations and discovery of the potential counterpart AT2024aawt
  2. GRB 241105A: VLT/FORS2 refined spectroscopic redshift z = 2.681
  3. LIGO/Virgo/KAGRA S241111bn: Identification of a GW compact binary merger candidate
  4. IPN triangulation of GRB 241107A (short/hard)
  5. GRB 241107A: INTEGRAL/IBIS/PICsIT detection of a short burst
  6. GRB 241025C: VZLUSAT-2 detection
  7. GRB 241025A: VZLUSAT-2 detection
  8. GRB 241018A: cubesat Avion detection
  9. GRB 241030B: TESS detection of optical counterpart
  10. LIGO/Virgo/KAGRA S241110br: Updated Sky localization
  11. LIGO/Virgo/KAGRA S241110br: Identification of a GW compact binary merger candidate
  12. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  13. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  14. EP241109a: KAIT photometry and 3 m Shane spectroscopy from Lick observatory
  15. LIGO/Virgo/KAGRA S241109bn: Updated Sky localization and EM Bright Classification
  16. EP241107a: AbAO optical upper limit
  17. LIGO/Virgo/KAGRA S241109bn: Upper limits from Fermi-GBM Observations
  18. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  19. LIGO/Virgo/KAGRA S241109p: Updated Sky localization and Source Classification
  20. LIGO/Virgo/KAGRA S241109bn: Identification of a GW compact binary merger candidate
  21. EP241109a: confirmation of a stellar flare by BOOTES-7
  22. LIGO/Virgo/KAGRA S241109p: Identification of a GW compact binary merger candidate
  23. EP241107A: MASTER optical observations of xray transient
  24. EP241107a: KAIT optical observations
  25. GRB 241108A: Swift ToO observations
  26. GRB 241030A: TESS observations
  27. GRB 241108A: COLIBRÍ Upper Limits on the Optical Counterpart
  28. EP241107a: Kinder optical follow-up observations
  29. GRB 241025A: radio detection with the VLA
  30. GRB 241104A: CALET Gamma-Ray Burst Monitor detection
  31. EP241107a: AKO Optical Afterglow Follow-Up Observations
  32. EP241107a: GSP detects optical counterpart
  33. EP241107a: Gemini-South spectroscopic confirmation (z = 0.456)
  34. GRB 241105A: EP-FXT follow-up observations
  35. GRB 241105A: SVOM/GRM observation
  36. EP241107a: OHP/T193 photometric and spectroscopic observations
  37. GRB 241105a: PRIME near-infrared upper limits
  38. EP241107a: FTW Optical and NIR observations of the optical counterpart
  39. GRB 241105A: ePESSTO+ NTT optical afterglow detection
  40. EP241107a: GIT optical observations
  41. EP241107a: Global MASTER-Net observations report
  42. EP241107a: SVOM/C-GFT optical observations
  43. EP241107a: AKO Optical Afterglow Detection
  44. GRB 241025A: LBT optical observations
  45. GRB241105A: Gemini-South Optical Afterglow Detection
  46. GRB 241105A: VLT/FORS2 optical afterglow rapid fading
  47. GRB 241105A: Swift/UVOT Detection
  48. EP241101a: CrAO ZTSH optical observations
  49. GRB 241105A: Swift/BAT-GUANO refined analysis of short burst with extended emission
  50. GRB 241030A: optical afterglow detection from the INAF Asiago Observatory
  51. GRB 241030A: Mondy optical observations
  52. GRB 241105A: Fermi GBM Observation of a Short Burst with Extended Emission
  53. Konus-Wind detection of GRB 241105A (short with extended emission)
  54. Konus-Wind detection of GRB 241021A
  55. GRB 241105A: SVOM/VT optical afterglow observations
  56. GRB 241105A: Swift-XRT afterglow detection
  57. GRB 241105A: VLT/FORS2 spectroscopic redshift z = 2.681
  58. GRB 241104A: Swift-XRT observations
  59. GRB 240511A: LCO upper limits
  60. GRB 241104A: Fermi GBM Observation
  61. GRB 241104A: The SVOM/VT candidate in GCN circular 38086 is not an astrophysical source
  62. GRB 241105A: Swift ToO observations
  63. GRB 241105A: Swift/BAT-GUANO arcminute localization of a short burst
  64. GRB 241104A: Swift ToO observations
  65. GRB 241104A: NOT optical non-detection
  66. GRB 241105A: GOTO tentative optical counterpart candidate
  67. Fermi GRB 241105A: Global MASTER-Net observations report
  68. GRB 241104A: SVOM/VT optical candidate
  69. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  70. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  71. GRB 241104A: SVOM/GRM observation
  72. EP241104a: EP detection of GRB 241104A X-ray emission
  73. GRB 241010A: host galaxy redshift z = 0.977
  74. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  75. GRB 241104A : Detection and localization by SVOM/ECLAIRs
  76. GRB 240821A: further radio observations with the VLA
  77. Fermi GRB 241104A: Global MASTER-Net observations report
  78. GRB 241030A: GRBAlpha detection
  79. EP241101a: EP-FXT observations update
  80. EP241103a: GIT optical upper limit
  81. EP241021a: OHP/T193 further optical observations
  82. LIGO/Virgo/KAGRA S241102br: OHP/T193 optical observations
  83. LIGO/Virgo/KAGRA S241102cy: Updated Sky localization
  84. EP241103a: GOTO optical upper limit
  85. LIGO/Virgo/KAGRA S241102br: Updated Sky localization
  86. EP241101a: Possible detection of an optical counterpart with FTW
  87. EP241103a: Swift XRT detection and improved X-ray position
  88. EP241021a: continued SOAR observations
  89. EP241101a: Optical upper limits with Kinder observations
  90. EP241101a: OHP/T193 optical observations
  91. EP241103a: Gemini optical limits
  92. EP241103a: EP observation update
  93. LIGO/Virgo/KAGRA S241102br: EP-WXT X-ray follow-up and flux limits
  94. GRB 241030A: Swift-UVOT observations of the optical prompt flare
  95. EP241103a: GSP optical upper limit
  96. EP241103A: LCO optical observations
  97. EP241103a: Global MASTER-Net observations report
  98. GRB 241030A: Rapid release of TESS data.
  99. EP241101a: Global MASTER-Net observations report
  100. GRB 241029A: GRBAlpha detection

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