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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"

22194 results found.

  1. IceCube Alert 241127.59: Global MASTER-Net observations report
  2. Swift GRB241127.91: Global MASTER-Net observations report
  3. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  4. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  5. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations (duplicate submission of 38345)
  6. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations (duplicate submission of 38345).
  7. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations
  8. EP241126a: Optical Upper limits with Kinder observations
  9. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  10. EP241126a: GSP detects optical counterpart
  11. EP241126a: TRT optical counterpart detection
  12. LIGO/Virgo/KAGRA S241127aj: Identification of a GW compact binary merger candidate
  13. EP241126a: EP detection of a fast X-ray transient
  14. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  15. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  16. Trigger_18947: Swift ToO observations (retracted)
  17. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  18. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  19. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  20. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  21. Konus-Wind detection of GRB 241115D / EP 241115a
  22. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  23. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  24. GRB 241026A: radio detection with the VLA
  25. EP241125a: Optical upper limit with Kinder observations
  26. EP241125a: EP detection of an X-ray transient
  27. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  28. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  29. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  30. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  31. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  32. GRB 241113B: SVOM/VT optical afterglow observations
  33. GRB 241105A: ATCA radio detection
  34. GRB241120A: OHP/T193 optical observations
  35. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  36. EP trigger ID 01709065118: Keck/LRIS spectroscopic observations
  37. EP-WXT trigger 01709018832: Lick/Kast spectroscopy with the 3 m Shane telescope
  38. GRB 241120A: Mondy and AbAO optical observations
  39. EP241119a: Optical upper limits with Kinder observations
  40. EP241119a: GIT optical upper limits
  41. GRB 241113A: Possible ATCA Radio detection
  42. EP241119a : J-band observations with WINTER
  43. Integral GRB241120.25: Global MASTER-Net observations report
  44. EP241119a: Global MASTER-Net observations report
  45. EP241119a: EP detection of a fast X-ray transient
  46. GRB 241112B: Mephisto further optical observations
  47. GRB 241030A: J-band observations
  48. GRB 241115a: PRIME near-infrared upper limits
  49. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  50. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  51. Fermi GRB 241118A: Global MASTER-Net observations report
  52. Fermi GRB 241117B: Global MASTER-Net observations report
  53. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  54. Fermi GRB 241117A: Global MASTER-Net observations report
  55. GRB 241115A: Swift-XRT afterglow detection
  56. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  57. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  58. Fermi GRB 241115B: Global MASTER-Net observations report
  59. EP241115a: Global MASTER-Net observations report
  60. EP241115a: EP detection of a fast X-ray transient
  61. EP241113a: No Detection in Fermi-GBM Observations
  62. Swift GRB 241115A: Global MASTER-Net observations report
  63. Fermi GRB 241115A: Global MASTER-Net observations report
  64. EP 241113a: LBT possible optical counterpart
  65. GRB 241113B: KAIT Optical Afterglow Candidate
  66. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  67. LIGO/Virgo/KAGRA S241114bi: Coverage and upper limits from MAXI/GSC observations
  68. GRB 241113A: PRIME near-infrared upper limits
  69. Fermi GRB 241114A: Global MASTER-Net observations report
  70. EP241113a: Global MASTER-Net observations report
  71. GRB 241113B: J-band upper limit from WINTER
  72. GRB 241113A: J-band observations with WINTER
  73. EP241113a : J-band observations with WINTER
  74. GRB 241030A: LCO optical observation
  75. GRB 241113B: Swift-XRT observations
  76. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  77. GRB 241113A: KAIT optical observations
  78. EP241113b: Global MASTER-Net observations report
  79. Fermi-LAT gamma-ray observations of IceCube-241113A
  80. EP241113a: EP on-board trigger and autonomous follow-up observation
  81. EP241107a: SOAR upper limits
  82. GRB 241113A: Swift/UVOT Detection
  83. GRB 241113A: REM detection of the optical/NIR afterglow
  84. GRB 241113B: Swift ToO observations
  85. GRB 241113A: LCO optical observations
  86. GRB241113A: LCOGT (40-cm) optical counterpart detection
  87. Swift GRB241113.33: Global MASTER-Net observations report
  88. Fermi trigger No 753166198: Global MASTER-Net observations report
  89. GRB 241105A: ATCA Radio Upper Limits
  90. GRB 241112B: AbAO optical upper limit
  91. GRB 241107A: GROWTH-India telescope optical upper limit
  92. IceCube Alert 241113.02: Global MASTER-Net observations report
  93. Fermi GRB 241112A: Global MASTER-Net observations report
  94. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  95. GRB 241112B: Swift-XRT afterglow detection
  96. GRB 241112B: SVOM/VT afterglow detection
  97. GRB 241112B: Mephisto optical upper limits
  98. GRB 241112B: GOTO optical upper limits
  99. GRB 241112B: Swift ToO observations
  100. EP241107a: EP-FXT follow-up observations

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