Cross-Dispersed Echelle Spectrograph

A high-resolution spectrometer available with TK3, a thin, grade 1, Tektronix 2048 x 2048 CCD. Two-pixel resolving powers in its two modes of operation are 60,000 (TS23) and up to 240,000 (TS21).

Two echelle gratings offer minimum inter-order separations of 10.5 and 15.5 arcsec. 

Co-addition is available. Remote field acquisition and guiding are available, and auto-guiding is available.

Instrument Characteristics

Detector(s):
TK3, a thin, grade 1, Tektronix 2048 x 2048 CCD (QE curve)

Wavelength coverage:
In TS23 mode: 3,400*–10,900 Å continuous, in as few as two exposures.
In TS21 mode: same available spectral range but 1/18 of the coverage of TS23

*Throughput falls off rapidly below 3600 Å.

Spectral resolving power:
TS23 has a resolving power of R~60,000 (depending on slit selection)
TS21 has a resolving power of up to R~240,000 (depending on slit selection) 

Throughput/sensitivity:

For TS23, signal/noise has been measured as:

V=6.03 K7V star with 575 sec exposure yields S/N = 470 @ 7480A, 220 @ 4800A

V=5.76 G1V star with 383 sec exposure yields S/N = 320 @7480A, 200 @ 4800A

V = 4.11 F8V star with 104 sec exposure yields S/N = 290 @7480A, 216 @ 4800A

S/N is per pixel

For TS21 and slit 3 (R~120,000), SNR=100 per resolution element is achieved for:
6 x 30-minute exposures at Ca II K (~4000 Å) with E1, 
2 x 30-minute exposures at K I (~7500 Å) with E1.
3 x 30-minute exposures at Na I D (~6000 Å) with E2.
 

Detailed Information About the Instrument and Its Uses

• Instrument Paper
• Introduction for New Users
• TS 2 User Manual

The following sub-manuals are referenced and linked in the User Manual and also are included here to be accessed individually. Click down arrow to show them.