ETC Request ID: STIS.sp.1013570

Exposure time (seconds) = 1,965.0000 at wavelength 1216.00 Å

gives: SNR = 14.3691 (per resolution element)


Table of Source and Noise Counts per Pixel

Plots

Detailed Information Count rate Total counts Associated noise
(counts/s) (counts) (counts)
Counts (box 7 pixels high) (1 pix x 7 pix) (2 pix resel x 7 pix)
    Source 0.076 299.16 17.30
    Background 0.001 4.13 2.03
        Sky 1.399e-14 5.50e-11 7.42e-06
        Dark Current 0.001 4.13 2.03
Total in selected region 0.077 303.28 20.82
Brightest Pixel (single exposure) (at 1216.15 Å) 0.034 67.78
Count rate entire detector 169.368
Buffer Time (sec) 11,808.59
For APT purposes, the recommended buffer time should be 4/5 of the buffer time calculated above. Please refer to the STIS Instrument Handbook for more details.
Global Count Rates
    Source only 5.269 10,354.415
    Background (sky+dark) 160.621 315,620.18
Encircled energy fraction 0.88

Instrument name: STIS
Mode: spectroscopic
Detector: FUVMAMA
Central Wavelength: 1425
Grating: [E140M] R ~ 45800
Aperture: 52X0.05
Glow region: low


Target: [point source]
Spectrum: User uploaded spectrum: GJ139_lyman_alpha_spectrum.txt
Extinction E(B-V): None
Normalization: None
Redshift: None
Emission Lines: None


Selected background:
  Sky Background:
    Level:

Table of Source and Noise Counts per Pixel

Plots

These results were computed using: ETC version 25.2