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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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').
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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"

3139 results found.

  1. LIGO/Virgo G194575: Near-infrared follow-up with OAO-WFC
  2. LIGO/Virgo G194575: Kanata/J-GEM optical follow-up
  3. LIGO/Virgo G194575: CQUEAN/LOAO observations
  4. LIGO Virgo G194575: MWA Observations
  5. LIGO/Virgo G194575: more details on transients from Pan-STARRS in the RA=1hr localisation region
  6. LIGO/Virgo G194575: Mini-MegaTORTORA observations
  7. GRB 151021A: MITSuME Okayama Ks-band upper-limit
  8. LIGO/Virgo G184098: TAROT network optical observations
  9. LIGO/Virgo G184098: iPTF Optical Transient Candidates
  10. LIGO/Virgo G184098: TAROT La Silla Observatory optical observations (TZAC)
  11. GRB 150915A: GROND detection of an optical counterpart candidate
  12. GRB 150907A: Swift-XRT afterglow detection
  13. GRB 150910A: MITSuME Ishigakijima Optical Observation after 1 day
  14. GRB 150910A: SAO RAS optical photometry
  15. Konus-Wind observation of GRB 150906B
  16. IPN Triangulation of GRB 150906B (short/intense)
  17. GRB 150907A: Swift-XRT observations
  18. ANTARES neutrino Alert150901.32 alert and Swift XRT counterpart: MASTER optical observations and new possible candidate
  19. Konus-Wind observation of GRB 150819B
  20. IPN Triangulation of GRB 150819B (short / very intense)
  21. GRB 150818A: Mondy optical observations
  22. GRB 150725A: MAXI/GSC detection
  23. Swift IGR J00291+5934: MASTER Optical flare detection
  24. Trigger 648422: Swift possible detection of a source in NGC4552
  25. Trigger 645944: Swift detection of H1745-203
  26. V404 Cyg: MASTER Swift, Integral alert observations
  27. GRB 150615A: Swift detection of a burst
  28. GRB150607A: Discovery Channel Telescope Optical Observations
  29. Konus-Wind observation of GRB 150607A
  30. Konus-Wind observation of GRB 150530A
  31. GRB 150530A: Fermi GBM observation
  32. GRB 150530A: Swift detection of a burst
  33. Konus-Wind observation of GRB 150523A
  34. GRB 150518A: MAXI-GSC further analysis
  35. Konus-Wind observation of GRB 150518A
  36. GRB 150518A: MAXI/GSC detection
  37. Swift Trigger 639636: a possible GRB
  38. GRB 150424A: Swift detection of a short burst
  39. GRB 150418A: Swift-XRT observations
  40. GRB 150403A: Swift-BAT refined analysis
  41. GRB 150403A: Swift/UVOT Detection
  42. GRB 150323C: Khureltogot optical observations
  43. GRB 150403A: Enhanced Swift-XRT position
  44. GRB 150403A: Swift detection of a burst with an optical counterpart
  45. GRB 150120B: GMG observation
  46. GRB 150323C: Mondy optical observations
  47. GRB 150323C: MASTER-net optical observation
  48. GRB 150318A: Skynet PROMPT-CTIO Observations
  49. GRB 150317A: Swift detection of a burst
  50. GRB 150313A: MAXI/GSC detection
  51. GRB 150305A: Swift XRT confirms weak INTEGRAL event as a new GRB
  52. GRB 150301C: XRT detection of a potential counterpart of BAT trigger 633105
  53. GRB 150302A: NOT afterglow candidate
  54. GRB 150302A: Swift detection of a burst
  55. GRB 150301A: GROND Observations
  56. GRB 150301A: Swift detection of a short burst or new SGR
  57. IPN Triangulation of GRB 150220A
  58. Trigger 631946: Swift detection of H1745-203
  59. Trigger 631747: Swift detection of 4U 0614+09
  60. GRB 150206B: Fermi GBM detection
  61. Swift Trigger 629693: probably not real
  62. GRB 150203A: P60 observations
  63. Swift Trigger 629206 is likely 1RXS J180408.9-342058
  64. GRB 150120B: Mondy optical observations
  65. Konus-Wind observation of GRB 150118B
  66. Trigger 626581: Swift detection of GRO J1008-57
  67. The Swift Detection of a Large Flare from the RS CVn Binary SZ Psc
  68. Swift detection of the variable star SZ Psc
  69. GRB 150110A: MAXI/GSC detection
  70. GRB 141220A: Swift-XRT refined Analysis
  71. GRB 141212A: MITSuME Okayama upper limits
  72. GRB 141207A: Swift-XRT afterglow candidate detection
  73. IPN Triangulation of GRB 141202A (short/hard)
  74. GRB 141121A: MITSuME Ishigakijima Optical Observation
  75. GRB 141121A: LCO-FTN observations
  76. GRB 141121A: MAXI/GSC detection
  77. IPN Triangulation of GRB 141118A
  78. GRB 141015A: TAROT La Silla observatory optical observations
  79. IPN Triangulation of GRB 141104A (long/very bright)
  80. GRB 141028A: SAO RAS Zeiss-1000 photometry
  81. GRB 141029B: Fermi GBM detection
  82. GRB 141022A: Swift detection of a burst
  83. Konus-Wind observation of GRB 141017A
  84. GRB 141017A: Zadko observatory - Gingin optical observations
  85. IPN Triangulation of GRB 141011A (short/hard)
  86. GRB 140930B: MASTER early possible OT detection
  87. GRB 140930B: MASTER early optical observations
  88. GRB 140930B: Swift detection of a short burst
  89. Konus-Wind observation of GRB 140928A
  90. GRB 140916A: Swift detection of a burst
  91. GRB 140907A : Optical observations from Nanshan
  92. GRB 140907A: Swift detection of a burst with an optical counterpart
  93. GRB 140903A: MAXI/GSC upper limit
  94. IPN Triangulation of GRB 140825A (very intense/long)
  95. GRB140819A: Deep GROND Upper Limits
  96. Fermi trigg_num 430148973: OSN I-band observations
  97. Swift trigger 609139 is probably 4U 1850-03
  98. GRB 140808A: Swift/UVOT Upper Limits
  99. Trigger 607399: Swift detection of SGR1806-20
  100. GRB 140719B, Swift-BAT refined analysis

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