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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"
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676 results found.

  1. INTEGRAL ToO OBSERVATIONS OF SGR1806-20: CALL FOR CORRELATED OBSERVATIONS
  2. Summary of recent IPN and HETE detections of SGR bursts
  3. Clarification of GCN 2354 on SGR1806-20
  4. IPN detection of continued activity from SGR1806-20
  5. 030813 SGR event (Konus-Wind observation)
  6. SGR 1808-20 (=H2802): A Possible new SGR
  7. SGR 1806-20, submm observations
  8. RXTE PCA Observations of SGR1806-20 Region
  9. HETE detection of burst from SGR1806-20
  10. GRB030329 observed as a sudden ionospheric disturbance (SID)
  11. IPN triangulation of GRB021219
  12. IPN detection of continued activity from SGR1806-20
  13. IPN detection of renewed activity from SGR1806-20
  14. IPN detection of continued SGR1900+14 activity
  15. IPN confirmation of the reactivation of SGR1900+14
  16. IPN detection of possible reactivation of SGR1900+14
  17. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  18. SGR1900+14 activity, November 2-4, 2002
  19. Detection of activity from SGR 1900+14 with the RXTE/PCA
  20. GRB021004: optical observations and predicted break time
  21. IPN detection of a burst from SGR1900+14
  22. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  23. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
  24. AXP 1E2259+586: quasi-simultaneous optical observation
  25. AXP 1E2259+586 optical observations
  26. SGR-like Bursts from the AXP 1E 2259+586
  27. IPN detection of possible bursts from SGR1806-20
  28. XRF 020427: Sudden Ionospheric Disturbance (SID)
  29. Mars Odyssey joins the IPN
  30. IPN detection and localization of Cygnus X-1 flares
  31. RXTE Observations of SGR 1900+14
  32. SGR1900+14 activity
  33. IPN/HETE Detection of Bursts from SGR1900+14
  34. IPN detection of further activity from SGR1806-20
  35. GRB 011121: Radio Observations
  36. The X-ray Flash 011030 ('GRB 011030')
  37. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  38. GRB010923 as seen by BeppoSAX GRBM
  39. Probable SGR or Short Duration GRB Detected by HETE
  40. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  41. Possible burst from SGR1806-20
  42. IPN detection of SGR1900+14
  43. X-ray precursors to the large flare from SGR 1900+14
  44. SGR 1900+14: No evidence of extended X-ray emission
  45. SGR 1900+14 : RXTE observations
  46. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  47. SGR1900+14
  48. SGR 1900+14: Correction to GCN 1049
  49. Millimeter observation of SGR 1900+14
  50. SGR 1900+14: Detection of extended X-ray emission
  51. Chandra Observations of SGR 1900+14
  52. SGR 1900+14, Chandra observations
  53. Chandra Observations of SGR 1900+14
  54. SGR1900+14, I-band observations
  55. SGR 1806-20 burst activity
  56. BATSE GRB trigger criteria
  57. Optical Observations of GRB990907
  58. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  59. GRB990308 not a new SGR
  60. GRB990308, Possible new SGR~0209+70
  61. SGR1900+14, BeppoSAX-GRBM observations
  62. GRB980703 optical followup
  63. SGR1627-41
  64. SGR1627-41, RXTE/ASM observations
  65. Reduced error box of SGR 1627-41
  66. SGR 1627-41
  67. Discovery of a new SGR source, SGR1627-41
  68. SGR 1900+14
  69. SGR1900+14
  70. SGR1900+14
  71. BATSE on-board GRB trigger change
  72. GRB980326 X-ray Observations
  73. GRB971214: Keck R & I-band Observations
  74. IRAS 18119-1342 and the possible new SGR
  75. Possible new SGR from US Naval Observatory
  76. RXTE Observations of SGR 1814-13

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