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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"

21106 results found.

  1. LIGO/Virgo S230611be: Global MASTER-Net observations report
  2. LIGO/Virgo S230611l: Global MASTER-Net observations report
  3. LIGO/Virgo S230609u: Global MASTER-Net observations report
  4. LIGO/Virgo S230608aw: Global MASTER-Net observations report
  5. LIGO/Virgo S230608as: Global MASTER-Net observations report
  6. LIGO/Virgo S230609a: Global MASTER-Net observations report
  7. LIGO/Virgo S230608ah: Global MASTER-Net observations report
  8. LIGO/Virgo S230608q: Global MASTER-Net observations report
  9. ZTF23aamxeqf/AT2023jxk: 1.3m DFOT Optical upper limit
  10. Fermi GRB 230603A: Global MASTER-Net observations report
  11. Fermi trigger No 707039690: Global MASTER-Net observations report
  12. ZTF and GIT Observations of the Candidate Optical Afterglow AT2023jxk
  13. LIGO/Virgo/KAGRA S230602ap: Zwicky Transient Facility observations
  14. GRB 230606A: Swift/UVOT Upper Limits
  15. LIGO/Virgo S230606z: Global MASTER-Net observations report
  16. LIGO/Virgo S230606d: Global MASTER-Net observations report
  17. Fermi-LAT gamma-ray observations of IceCube-230603A
  18. LIGO/Virgo S230605o: Global MASTER-Net observations report
  19. LIGO/Virgo S230604z: Global MASTER-Net observations report
  20. LIGO/Virgo S230603aa: Global MASTER-Net observations report
  21. LIGO/Virgo S230602ap: Global MASTER-Net observations report
  22. LIGO/Virgo S230601bf: Global MASTER-Net observations report
  23. LIGO/Virgo S230531f: Global MASTER-Net observations report
  24. LIGO/Virgo/KAGRA S230529ay: Zwicky Transient Facility observations
  25. LIGO/Virgo/KAGRA S230528a: Zwicky Transient Facility observations
  26. LIGO/Virgo/KAGRA S230527ch: Zwicky Transient Facility observations
  27. LIGO/Virgo/KAGRA S230529ay: Upper limits from CALET observations.
  28. LIGO/Virgo S230529ay: Global MASTER-Net observations report
  29. LIGO/Virgo/KAGRA S230529ay: Coverage and upper limits from MAXI/GSC observations
  30. LIGO/Virgo/KAGRA S230529ay: Upper limits from Fermi-GBM Observations
  31. LIGO/Virgo S230529p: Global MASTER-Net observations report
  32. Alert from the HAWC Burst Monitor HAWC-230527A
  33. LIGO/Virgo S230525a: Global MASTER-Net observations report
  34. Fermi-LAT gamma-ray observations of IceCube-230524A
  35. LIGO/Virgo/KAGRA S230518h: Upper limits from Glowbug gamma-ray observations
  36. LIGO/Virgo/KAGRA S230518h: TESS observations of the localization region
  37. IceCube Alert 230524.47: Global MASTER-Net observations report
  38. LIGO/Virgo/KAGRA S230518h: No transient candidates in CALET observations
  39. Fermi trigger No 706610076: Global MASTER-Net observations report
  40. LIGO/Virgo S230524b: Global MASTER-Net observations report
  41. Fermi trigger No 706599831: Global MASTER-Net observations report
  42. Fermi trigger No 706536788: Global MASTER-Net observations report
  43. LIGO/Virgo/KAGRA S230521k: MASTER new OT discovery
  44. LIGO/Virgo/KAGRA S230521k: Additional candidates from Zwicky Transient Facility
  45. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230523A
  46. LIGO/Virgo S230522n: Global MASTER-Net observations report
  47. LIGO/Virgo S230522a: Global MASTER-Net observations report
  48. LIGO/Virgo/KAGRA S230518h: Swift/UVOT Upper Limits for MeerLICHT candidates: AT2023ixg and AT2023iyb
  49. LIGO/Virgo S230521k: Global MASTER-Net observations report
  50. LIGO/Virgo/KAGRA S230521k: Zwicky Transient Facility observations
  51. LIGO/Virgo S230520ae: Global MASTER-Net observations report
  52. Fermi trigger No 706328428: Global MASTER-Net observations report
  53. Fermi trigger No 706331483: Global MASTER-Net observations report
  54. Fermi trigger No 706317104: Global MASTER-Net observations report
  55. LIGO/Virgo/KAGRA S230518h: ATCA follow-up of candidate counterparts
  56. LIGO/Virgo/KAGRA S230518h: GECKO tiling observations with KMTNet
  57. LIGO/Virgo/KAGRA S230518h: Swift/UVOT Upper Limits for Swope candidates: SSS23a, SSS23b and SSS23c
  58. LIGO/Virgo/KAGRA S230518h: ATLAS observations of the skymap
  59. LIGO/Virgo/KAGRA S230518h: Swope Search and Candidate Counterpart Identification
  60. LIGO/Virgo/KAGRA S230518h: Upper limits from Konus-Wind observations
  61. LIGO/Virgo S230518h: AGILE/MCAL observations
  62. LIGO/Virgo S230518h: Swift XRT observations, 8 X-ray sources
  63. LIGO/Virgo/KAGRA S230518h: Coverage and upper limits from MAXI/GSC observations
  64. LIGO/Virgo/Kagra S230518h: NED Galaxies in the Localization Volume
  65. LIGO/Virgo/KAGRA S230518h: Upper limits from Fermi-GBM Observations
  66. LIGO/Virgo S230518h: Global MASTER-Net observations report
  67. GRB 230513A: Zwicky Transient Facility continuous observations of a Fermi Short GRB (Trigger 705709044)
  68. Fermi trigger No 706014351: Global MASTER-Net observations report
  69. Fermi trigger No 705952199: Global MASTER-Net observations report
  70. GRB 230512A: Liverpool Telescope observations
  71. GRB 230512A: GIT non detection of afterglow candidate
  72. GRB 230512A: Kitab possible afterglow candidate
  73. Fermi trigger No 705565670: Global MASTER-Net observations report
  74. Fermi-LAT gamma-ray observations of IceCube-230511A
  75. GRB 230510A: OHP/T193 and OHP/T120 optical observations
  76. GRB 230512A: Swift-XRT observations
  77. GRB 230512A: GIT optical follow-up ZTF candidates
  78. GRB 230430A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 704533643)
  79. GRB 230511D: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705537623)
  80. GRB 230512A: Tiled Swift observations
  81. GRB 230510A: GIT optical upper limits
  82. GRB 230510A: Swift/UVOT Observations
  83. Fermi trigger No 705503315: Global MASTER-Net observations report
  84. Fermi trigger No 705496510: Global MASTER-Net observations report
  85. Fermi trigger No 705446499: Global MASTER-Net observations report
  86. GRB 230510A: Gaoyazi/GOT optical upper limit
  87. GRB 230510A: Nanshan/NEXT optical afterglow detection
  88. Fermi trigger No 705413051: Global MASTER-Net observations report
  89. GRB 230506C: SAO RAS optical observations
  90. GRB 230307A: JWST second-epoch observations
  91. Fermi-LAT gamma-ray observations of IceCube-230506A
  92. GRB 230506C: spectro-imaging observations of the optical afterglow with T193-OHP
  93. GRB 230506C: Swift/UVOT Upper Limits
  94. GRB 230506C: NUTTelA-TAO / BSTI Early Optical Limits
  95. GRB 230506B: Swift/UVOT Detection
  96. Swift GRB230506.71: Global MASTER-Net observations report
  97. GRB 230506B: MASTER optical observations
  98. Fermi trigger No 704837952: Global MASTER-Net observations report
  99. GRB 230427A: NOT optical upper limit
  100. GRB 230427A: Swift/UVOT Detection

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