ETC Request ID: STIS.sp.1184902

Exposure time (seconds) = 1,034.0000 at wavelength 1400.00 Å

gives: SNR = 56.3302 (per resolution element)

Exposure time calculation HAD WARNINGS.

WARNING MESSAGE: MAMA Bright limits: total count rate per image 82432.4 exceeds limit for irregularly-variable sources 40 percent of the bright limit 200000 counts per second

WARNING MESSAGE: Buffer time 24.2623 is less than minimum 99 seconds.


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 1.732 3,581.61 59.85
    Background 0.001 2.17 1.47
        Sky 3.172e-15 6.56e-12 2.56e-06
        Dark Current 0.001 2.17 1.47
Total in selected region 1.733 3,583.78 63.58
Brightest Pixel (single exposure) (at 1320.10 Å) 0.802 829.33
Count rate entire detector 82,432.446
Buffer Time (sec) 24.26
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 51,745.647 53,504,999.476
    Background (sky+dark) 157.286 162,634.14
Encircled energy fraction 0.93

Instrument name: STIS
Mode: spectroscopic
Detector: FUVMAMA
Central Wavelength: 1416
Grating: [E140H] R ~ 114000
Aperture: 0.2X0.09
Glow region: low


Target: [point source]
Spectrum: Standard HST Star Spectra BD+28°4211 (Op, 10.51) [1140.6, 10242.7 Å]
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 26.1