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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"

26119 results found.

  1. GRB 241112B: Mephisto further optical observations
  2. GRB 241115a: PRIME near-infrared upper limits
  3. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  4. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  5. GRB 241115B: Fermi GBM Observation
  6. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  7. GRB 241115C: Fermi GBM Observation
  8. GRB 241115A: Swift-XRT afterglow detection
  9. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  10. GRB 241113B: Mephisto upper limits
  11. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  12. EP241113a: Swift XRT weak detection
  13. GRB 241115A: Fermi GBM Observation
  14. GRB 241115A: LCOGT Optical Upper Limits
  15. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  16. Swift GRB 241115A: Global MASTER-Net observations report
  17. GRB 241115A: Swift detection of a burst
  18. EP 241113a: LBT possible optical counterpart
  19. GRB 241113B: KAIT Optical Afterglow Candidate
  20. GRB 241113A: Swift-BAT refined analysis
  21. GRB 241113A: PRIME near-infrared upper limits
  22. GRB 241113A: J-band observations with WINTER
  23. GRB 241113B: Swift-XRT observations
  24. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  25. GRB 241113A: KAIT optical observations
  26. GRB 241113A: Swift-XRT refined Analysis
  27. GRB 241113A: Swift/UVOT Detection
  28. GRB 241113A: REM detection of the optical/NIR afterglow
  29. Konus-Wind detection of GRB 241107A (short/hard)
  30. GRB 241113B: Swift ToO observations
  31. GRB 241113A: LCO optical observations
  32. GRB 241113A: Enhanced Swift-XRT position
  33. GRB241113A: LCOGT (40-cm) optical counterpart detection
  34. GRB 241113A: MASTER010615.66-224018.2 optical counterpart detection
  35. GRB 241113A: Swift detection of a burst with an optical counterpart
  36. Swift GRB241113.33: Global MASTER-Net observations report
  37. GRB 241112B: AbAO optical upper limit
  38. GRB 241107A: GROWTH-India telescope optical upper limit
  39. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  40. GRB 241112B: Swift-XRT afterglow detection
  41. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  42. GRB 241112B: SVOM/VT afterglow detection
  43. GRB 241107A: Swift/BAT candidate arcminute localization of a short burst
  44. GRB 241112B: Swift ToO observations
  45. GRB 241107A: INTEGRAL IBIS localization
  46. GRB 241105A: VLT/FORS2 refined spectroscopic redshift z = 2.681
  47. IPN triangulation of GRB 241107A (short/hard)
  48. GRB 241025A: VZLUSAT-2 detection
  49. GRB 241030B: TESS detection of optical counterpart
  50. EP241107a: AbAO optical upper limit
  51. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  52. GRB 241108A: Swift-XRT observations
  53. EP241107A: MASTER optical observations of xray transient
  54. EP241107a: KAIT optical observations
  55. GRB 241108A: Swift ToO observations
  56. GRB 241030A: TESS observations
  57. EP241107a: Kinder optical follow-up observations
  58. EP241107a: AKO Optical Afterglow Follow-Up Observations
  59. GRB 241105A: EP-FXT follow-up observations
  60. GRB 241105A: SVOM/GRM observation
  61. GRB 241105a: PRIME near-infrared upper limits
  62. GRB 241105A: ePESSTO+ NTT optical afterglow detection
  63. EP241107a: GIT optical observations
  64. EP241107a: AKO Optical Afterglow Detection
  65. GRB 241025A: LBT optical observations
  66. GRB241105A: Gemini-South Optical Afterglow Detection
  67. GRB 241105A: VLT/FORS2 optical afterglow rapid fading
  68. GRB 241105A: Swift/UVOT Detection
  69. GRB 241105A: Swift/BAT-GUANO refined analysis of short burst with extended emission
  70. GRB 241030A: optical afterglow detection from the INAF Asiago Observatory
  71. GRB 241105A: BOOTES-7 optical detection
  72. GRB 241030A: Mondy optical observations
  73. GRB 241105A: Fermi GBM Observation of a Short Burst with Extended Emission
  74. GRB 241105A: SVOM/VT optical afterglow observations
  75. GRB 241105A: Swift-XRT afterglow detection
  76. GRB 241104A: Swift-XRT observations
  77. GRB 241105A: Swift ToO observations
  78. GRB 241105A: Swift/BAT-GUANO arcminute localization of a short burst
  79. GRB 241104A: Swift ToO observations
  80. GRB 241104A: SVOM/VT optical candidate
  81. GRB 241010A: host galaxy redshift z = 0.977
  82. GRB 241030A: GRBAlpha detection
  83. EP241103a: GIT optical upper limit
  84. EP241103a: GOTO optical upper limit
  85. EP241103a: Swift XRT detection and improved X-ray position
  86. GRB 241030A: Swift-UVOT observations of the optical prompt flare
  87. GRB 241030A: Rapid release of TESS data.
  88. EP241030a: Futher EP-FXT observation of the X-ray Afterglow of GRB 241030A
  89. Swift GRB 241101A: Global MASTER-Net observations report
  90. GRB 241101A: FRAM-ORM optical limit
  91. GRB 241101A: Swift-BAT refined analysis
  92. GRB 241030B: Swift-XRT refined Analysis
  93. GRB 241030A / EP241030a: GMG possible spectroscopic redshift at z ~ 1.4
  94. EP241030a: EP/FXT observation of GRB 241030A X-ray Afterglow
  95. GRB 241101A: Swift detection of a burst
  96. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  97. GRB 241030B: Montarrenti Observatory optical upper limit
  98. GRB 241030A / EP241030a: FTW Optical and NIR observations of the optical counterpart
  99. GRB 241030A: Fermi GBM Observation
  100. GRB 241030B: LCOGT Optical Upper Limits

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