{"id":2014,"date":"2021-12-14T11:15:14","date_gmt":"2021-12-14T10:15:14","guid":{"rendered":"https:\/\/stel.asu.cas.cz\/en\/?page_id=2014"},"modified":"2026-03-16T14:44:52","modified_gmt":"2026-03-16T13:44:52","slug":"single-order-spectrograph","status":"publish","type":"page","link":"https:\/\/stel.asu.cas.cz\/en\/telescope\/instrumentation\/single-order-spectrograph\/","title":{"rendered":"Single order spectrograph"},"content":{"rendered":"\n

Single order (formerly coud\u00e9 spectrograph or ‘CCD700’ spectrograph) is fiber fed medium resolution spectrograph working in the first and second spectral orders. Wavelength coverage of the second order is 3660-5100 \u00c5 (near UV to blue) with order length of 233 \u00c5; wavelength coverage of the first order is 5100-8900 \u00c5 (green to near IR) with order length of 470 \u00c5. Resolving power is \u223c12 200 in blue spectral ragion (Balmer jump) and \u223c10 800 in red (H\u03b1) spectral region. The camera features the PyLoN 2048x512BX (E2V 42-10 BX) CCD detector (cooled by liquid nitrogen to -115\u00b0C) with a pixel size of 13.5 \u03bcm. The main advantage is that it depicts wide interval of wavelengths (475\u00a0\u00c5 in the H\u03b1 spectral region) with uniform S\/N. More information about technical specification and calibration can be found here<\/a><\/strong>.<\/p>\n\n\n\n

Camera main characteristics<\/mark><\/h5>\n\n\n
\n\n\n\n\n
Camera<\/strong><\/td>\nChip<\/strong><\/td>\nDimension<\/strong><\/td>\nPixel size<\/strong><\/td>\nReading<\/strong><\/td>\n<\/tr>\n
PyLoN<\/strong><\/a><\/td>\nE2V 42-10 BX<\/strong><\/td>\n2048×512<\/strong><\/td>\n13.5 x 13.5 <\/strong>\u03bcm<\/strong><\/td>\n19 s<\/strong><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/figure>\n\n\n
Spectrograph main characteristics<\/mark><\/h5>\n\n\n\n

The single order spectrograph works in two spectral orders – first order in red part of the spectra (approx. from 5100 \u00c5 to the IR), and second order in blue part (from approx. 3660 \u00c5 to approx. 5 100 \u00c5).<\/p>\n\n\n

\n\n\n\n\n
\n

1st order
<\/strong><\/p>\n<\/td>\n

\n

Order length<\/strong><\/p>\n<\/td>\n

\n

Resolution<\/strong><\/p>\n<\/td>\n

\u00a0<\/td>\n<\/tr>\n
5100-8900 \u00c5<\/strong><\/td>\n470 \u00c5<\/strong><\/td>\n~10 800 (H<\/strong>\u03b1)<\/strong><\/td>\n\u00a0<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/figure>\n
\n\n\n\n\n
\n

2nd order
<\/strong><\/p>\n<\/td>\n

\n

Order length
<\/strong><\/p>\n<\/td>\n

\n

Resolution<\/strong><\/p>\n<\/td>\n

\u00a0<\/td>\n<\/tr>\n
3660-5100 \u00c5<\/strong><\/td>\n233 \u00c5<\/strong><\/td>\n~12 200 (Balmer jump<\/strong>)<\/strong><\/td>\n\u00a0<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/figure>\n\n\n

The length of the spectral interval in the first order is approx. 470\u00a0\u00c5, the length in the second order is approx. 233\u00a0\u00c5 (ratio approx. 2:1). The resolving power in the first order is approx. 10 800 (around H-alpha line), in the second order approx. 12\u00a0200 (at Balmer jump).<\/p>\n\n\n\n

Example of spectral ranges<\/h5>\n\n\n\n
Balmer jump<\/strong><\/td>H-gamm<\/strong><\/strong>a<\/strong><\/td>H-beta<\/strong><\/strong><\/strong><\/td>H-alpha<\/strong><\/strong><\/strong><\/td>GAIA<\/strong><\/strong><\/strong><\/td><\/tr>
3665-3920 \u00c5<\/td>4272-4506 \u00c5<\/td>4757-4990 \u00c5<\/td>6260-6765 \u00c5<\/td>8400-8870 \u00c5<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

The final spectral range during observation is adjustable on request. <\/p>\n\n\n\n

Optical layout<\/span><\/strong><\/h5>\n\n\n\n