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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"

21097 results found.

  1. Fermi GRB 230603A: Global MASTER-Net observations report
  2. Fermi trigger No 707039690: Global MASTER-Net observations report
  3. ZTF and GIT Observations of the Candidate Optical Afterglow AT2023jxk
  4. LIGO/Virgo/KAGRA S230602ap: Zwicky Transient Facility observations
  5. GRB 230606A: Swift/UVOT Upper Limits
  6. LIGO/Virgo S230606z: Global MASTER-Net observations report
  7. LIGO/Virgo S230606d: Global MASTER-Net observations report
  8. Fermi-LAT gamma-ray observations of IceCube-230603A
  9. LIGO/Virgo S230605o: Global MASTER-Net observations report
  10. LIGO/Virgo S230604z: Global MASTER-Net observations report
  11. LIGO/Virgo S230603aa: Global MASTER-Net observations report
  12. LIGO/Virgo S230602ap: Global MASTER-Net observations report
  13. LIGO/Virgo S230601bf: Global MASTER-Net observations report
  14. LIGO/Virgo S230531f: Global MASTER-Net observations report
  15. LIGO/Virgo/KAGRA S230529ay: Zwicky Transient Facility observations
  16. LIGO/Virgo/KAGRA S230528a: Zwicky Transient Facility observations
  17. LIGO/Virgo/KAGRA S230527ch: Zwicky Transient Facility observations
  18. LIGO/Virgo/KAGRA S230529ay: Upper limits from CALET observations.
  19. LIGO/Virgo S230529ay: Global MASTER-Net observations report
  20. LIGO/Virgo/KAGRA S230529ay: Coverage and upper limits from MAXI/GSC observations
  21. LIGO/Virgo/KAGRA S230529ay: Upper limits from Fermi-GBM Observations
  22. LIGO/Virgo S230529p: Global MASTER-Net observations report
  23. Alert from the HAWC Burst Monitor HAWC-230527A
  24. LIGO/Virgo S230525a: Global MASTER-Net observations report
  25. Fermi-LAT gamma-ray observations of IceCube-230524A
  26. LIGO/Virgo/KAGRA S230518h: Upper limits from Glowbug gamma-ray observations
  27. LIGO/Virgo/KAGRA S230518h: TESS observations of the localization region
  28. IceCube Alert 230524.47: Global MASTER-Net observations report
  29. LIGO/Virgo/KAGRA S230518h: No transient candidates in CALET observations
  30. Fermi trigger No 706610076: Global MASTER-Net observations report
  31. LIGO/Virgo S230524b: Global MASTER-Net observations report
  32. Fermi trigger No 706599831: Global MASTER-Net observations report
  33. Fermi trigger No 706536788: Global MASTER-Net observations report
  34. LIGO/Virgo/KAGRA S230521k: MASTER new OT discovery
  35. LIGO/Virgo/KAGRA S230521k: Additional candidates from Zwicky Transient Facility
  36. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230523A
  37. LIGO/Virgo S230522n: Global MASTER-Net observations report
  38. LIGO/Virgo S230522a: Global MASTER-Net observations report
  39. LIGO/Virgo/KAGRA S230518h: Swift/UVOT Upper Limits for MeerLICHT candidates: AT2023ixg and AT2023iyb
  40. LIGO/Virgo S230521k: Global MASTER-Net observations report
  41. LIGO/Virgo/KAGRA S230521k: Zwicky Transient Facility observations
  42. LIGO/Virgo S230520ae: Global MASTER-Net observations report
  43. Fermi trigger No 706328428: Global MASTER-Net observations report
  44. Fermi trigger No 706331483: Global MASTER-Net observations report
  45. Fermi trigger No 706317104: Global MASTER-Net observations report
  46. LIGO/Virgo/KAGRA S230518h: ATCA follow-up of candidate counterparts
  47. LIGO/Virgo/KAGRA S230518h: GECKO tiling observations with KMTNet
  48. LIGO/Virgo/KAGRA S230518h: Swift/UVOT Upper Limits for Swope candidates: SSS23a, SSS23b and SSS23c
  49. LIGO/Virgo/KAGRA S230518h: ATLAS observations of the skymap
  50. LIGO/Virgo/KAGRA S230518h: Swope Search and Candidate Counterpart Identification
  51. LIGO/Virgo/KAGRA S230518h: Upper limits from Konus-Wind observations
  52. LIGO/Virgo S230518h: AGILE/MCAL observations
  53. LIGO/Virgo S230518h: Swift XRT observations, 8 X-ray sources
  54. LIGO/Virgo/KAGRA S230518h: Coverage and upper limits from MAXI/GSC observations
  55. LIGO/Virgo/Kagra S230518h: NED Galaxies in the Localization Volume
  56. LIGO/Virgo/KAGRA S230518h: Upper limits from Fermi-GBM Observations
  57. LIGO/Virgo S230518h: Global MASTER-Net observations report
  58. GRB 230513A: Zwicky Transient Facility continuous observations of a Fermi Short GRB (Trigger 705709044)
  59. Fermi trigger No 706014351: Global MASTER-Net observations report
  60. Fermi trigger No 705952199: Global MASTER-Net observations report
  61. GRB 230512A: Liverpool Telescope observations
  62. GRB 230512A: GIT non detection of afterglow candidate
  63. GRB 230512A: Kitab possible afterglow candidate
  64. Fermi trigger No 705565670: Global MASTER-Net observations report
  65. Fermi-LAT gamma-ray observations of IceCube-230511A
  66. GRB 230510A: OHP/T193 and OHP/T120 optical observations
  67. GRB 230512A: Swift-XRT observations
  68. GRB 230512A: GIT optical follow-up ZTF candidates
  69. GRB 230430A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 704533643)
  70. GRB 230511D: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705537623)
  71. GRB 230512A: Tiled Swift observations
  72. GRB 230510A: GIT optical upper limits
  73. GRB 230510A: Swift/UVOT Observations
  74. Fermi trigger No 705503315: Global MASTER-Net observations report
  75. Fermi trigger No 705496510: Global MASTER-Net observations report
  76. Fermi trigger No 705446499: Global MASTER-Net observations report
  77. GRB 230510A: Gaoyazi/GOT optical upper limit
  78. GRB 230510A: Nanshan/NEXT optical afterglow detection
  79. Fermi trigger No 705413051: Global MASTER-Net observations report
  80. GRB 230506C: SAO RAS optical observations
  81. GRB 230307A: JWST second-epoch observations
  82. Fermi-LAT gamma-ray observations of IceCube-230506A
  83. GRB 230506C: spectro-imaging observations of the optical afterglow with T193-OHP
  84. GRB 230506C: Swift/UVOT Upper Limits
  85. GRB 230506C: NUTTelA-TAO / BSTI Early Optical Limits
  86. GRB 230506B: Swift/UVOT Detection
  87. Swift GRB230506.71: Global MASTER-Net observations report
  88. GRB 230506B: MASTER optical observations
  89. Fermi trigger No 704837952: Global MASTER-Net observations report
  90. GRB 230427A: NOT optical upper limit
  91. GRB 230427A: Swift/UVOT Detection
  92. GRB 230427A: Gaoyazi/GOT optical upper limit
  93. GRB 230427A: OHP/T193 spectroscopy observations of WISEA J101316.01+481158.7
  94. GRB 230427A: Nanshan/HMT optical upper limit
  95. GRB 230427A: Osservatorio Astronomico Nastro verde upper limit
  96. GRB 230427A: OSIRIS+/GTC observations
  97. Fermi trigger No 704365743: Global MASTER-Net observations report
  98. GRB 230427A: GIT optical upper limit
  99. GRB 230427A: Bassano Bresciano Observatory upper limit
  100. Swift GRB230427.44: Global MASTER-Net observations report

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