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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.

"N/A_MC170405_R1" does not adhere to advanced search syntax. Please refer to the documentation and try again.
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"

10959 results found.

  1. IceCube-260315A/AT2026fpm: EP-FXT follow-up observation
  2. EP260316a / GRB 260316A: SVOM/VT optical upper limits
  3. EP260316a: optical upper limit with Kinder observations
  4. EP260314a: optical upper limit with Kinder observations
  5. EP260314a: SVOM/VT optical candidate
  6. GRB 260310A / AT2026fgk: SAO RAS optical observations
  7. GRB 260310A / AT2026fgk: Multiband optical follow-up with Kinder observations
  8. GRB 260310A: NOT optical polarimetry
  9. GRB 260310A/AT 2026fgk: Bok spectroscopic observation
  10. GRB 260310A / AT2026fgk: OSIRIS+/GTC spectroscopy confirms redshift z = 0.153
  11. GRB 260307A: CALET Gamma-Ray Burst Monitor detection
  12. GRB 260312A: Swift detection of a burst
  13. GRB 260131A/B: radio detection with the VLA
  14. EP260306a: Mondy optical upper limit
  15. GRB 260208A: radio detection with the VLA
  16. GRB 260307B: SVOM/VT upper limit with X band data analysis
  17. GRB 260307B: SVOM/VT optical candidate
  18. EP260302a: SVOM/VT optical observation
  19. EP260306a: Gemini-North redshift z = 4.773
  20. EP260306a: SVOM/VT optical observation
  21. EP260302a: Gemini-South redshift z = 1.535
  22. GRB 260211A: SVOM/VT optical rebrightening at 20 days after the burst, SN candidate
  23. GRB 260303A: SVOM/VT optical observations
  24. GRB 260303A: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
  25. EP260227a: Mondy optical observations
  26. EP260227a: SVOM/VT optical observation
  27. GRB 260228A: SVOM/VT optical upper limits
  28. EP260227A: 3.6m DOT optical afterglow detection
  29. EP260227a: likely GTC/OSIRIS+ redshift z = 2.714
  30. EP260227a: Liverpool Telescope observations
  31. GRB 260225A: SVOM/VT optical continued observations and upper limit
  32. EP/WXT trigger 01709258681 (EP260227a?): LCO candidate afterglow
  33. GRB 260223A: 7DT detection and Medium-band SED of Afterglow
  34. EP260214a: VLT/FORS2 optical observations
  35. GRB 260226A: CALET Gamma-Ray Burst Monitor detection
  36. EP260214a: VLA 6 GHz detection
  37. GRB 260225A: SVOM/VT optical observation
  38. GRB 260225A: SVOM/COLIBRÍ (FM-GFT) Detection of an Optical Counterpart Candidate
  39. GRB 260225A: SVOM/VT optical upper limits
  40. EP260126a: VLA 6 GHz detection
  41. EP260223a: Liverpool Telescope upper limits
  42. GRB 260225A: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  43. EP260223a: Xinglong optical upper limit
  44. sb26021801: SVOM/VT optical upper limits
  45. GRB 260223A: SVOM/VT optical observation
  46. EP260221a: Optical upper limit with Kinder observations
  47. EP260214b: Mondy optical observations
  48. EP260210a: Mondy optical upper limits
  49. GRB 260208A: AbAO and Terskol optical upper limits
  50. GRB 260208A: continued Mondy optical observations
  51. EP260214b: Optical upper limit with Kinder observations
  52. EP260214a: Optical upper limits with Kinder observations
  53. EP260214a: VLT near-infrared observation
  54. EP260214b: SVOM/VT optical observation
  55. EP260214b: OHP/T120 optical observations
  56. EP260214b: VLT/X-shooter spectroscopic redshift z = 1.208
  57. GRB 260211A: SVOM/VT optical counterpart
  58. EP260214a: SVOM/VT optical upper limits
  59. EP260213a: Optical upper limits with Kinder observations
  60. EP260213a: SVOM/VT optical upper limit
  61. EP260213a: Mondy R-band optical upper limit
  62. GRB 260211A: SVOM/VT optical observation
  63. GRB 260211A: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  64. EP260210a: Optical upper limits with Kinder observations
  65. EP260210a: SVOM/VT optical upper limit
  66. GRB 260208B: refined analysis of the EP-FXT observation
  67. GRB 260131A/B: continued Mondy optical observations
  68. GRB 260208A: Mondy optical observations
  69. GRB 260208B: EP-FXT observation
  70. GRB 260208B: SVOM/VT optical candidate
  71. GRB 260208A: SVOM/VT optical observation
  72. GRB 260208A : MASTER bright optical transient inside retracted Fermi error-box
  73. GRB 260207A : MASTER optical counterpart discovery
  74. GRB 260131A/B: Mondy and Terskol optical observations
  75. GRB 260206A (or XRB from 4U 0513-40): MAXI/GSC detection
  76. GRB 260204A: SVOM/VT confirms fading of the optical afterglow
  77. GRB 260204A: SVOM/VT optical candidate
  78. GRB 260204A : MASTER Global robotic net optical observations
  79. GRB 260131A/B: OHP/T193 optical observations
  80. EP260131a: SVOM/VT optical observation
  81. EP260131a: VLT/X-shooter spectroscopic redshift z = 0.937
  82. EP260131a: NOT early detection of the counterpart in "rapid response mode"
  83. GRB 260131B: MAXI/GSC detection
  84. GRB 260128B: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  85. GRB 260127A: INASAN-Kislovodsk, SAO RAS, and Terskol K-800 optical observations
  86. EP260128a: NOT optical counterpart candidate
  87. EP260128a: LCO optical upper limits
  88. EP260126a: SVOM/VT optical upperlimit
  89. GRB 260127A: Fermi GBM Observation
  90. GRB 260127A : MITSuME Akeno optical afterglow candidate detection
  91. Swift GRB 260127A: Global MASTER-Net observations report
  92. GRB 260127A: Swift detection of a burst
  93. EP260126a: Optical upper limit with Kinder observations
  94. EP260126a: Liverpool Telescope optical upper limits
  95. EP260126a: Further NOT optical upper limits
  96. GRB 260114A: SVOM/VT optical upper limits
  97. EP260119a: Assy AZT-20 optical observations
  98. EP260119a: Mondy and SAO RAS optical upper limits
  99. EP260119A: Mondy I-Band Observations
  100. GRB 251202A: further radio observations with the VLA

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