ETC Request ID: STIS.sp.840261

Exposure time (seconds) = 2,048.0000 at wavelength 2500.00 Å

gives: SNR = 3.8644 (per resolution element)

gives: Time to Saturation (for a single exposure) = 4,321.35 seconds

Exposure time calculation HAD WARNINGS.

WARNING MESSAGE: "Electrons per pixel due to background (4.9) is less than the recommended threshold of 20 electrons to avoid poor charge transfer efficiency (CTE). We suggest you consider CTE mitigation strategies described in the STIS Instrument Handbook."


Table of Source and Noise Counts per Pixel


Plots


Detailed Information Count rate Total counts Associated noise
(e-/s) (e-) (e-)
Counts (box 7 pixels high) (1 pix x pix) (2.0 pix resel x pix)
    Source 0.068 276.69 16.63
    Background 0.133 544.77 23.34
        Sky 1.458e-06 5.97e-03 0.08
        Dark Current 0.133 544.77 23.34
    Read Out 65.61
Total in selected region 0.201 821.47 71.60
Brightest Pixel (single exposure) (at 2796.00 Å) 7.637 1,954.95

Global Count Rates
    Source only 186.532 382,017.183
    Background (sky+dark) 19,928.186 40,812,925.66

Encircled energy fraction 0.95


Instrument name: STIS
Mode: spectroscopic
Detector: CCD
Central Wavelength:
Grating: [G230LB] R ~ 700
Aperture: 52X0.2
Gain: 1.0
# Frames: 8
Binning: dispersion: 1, spatial: 1
Dark:


Target: [point source]
Spectrum: User uploaded spectrum: spec.dat
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 24.2