##language:en #pragma section-numbers off <> '''Note that this page is no longer maintained. It has been replaced by a new page [[http://iram-institute.org/EN/content-page.php?ContentID=58&rub=7&srub=55&ssrub=58&sssrub=0&ssssrub=0|here]].(ck, 7.7.09).''' ------ ------ ------ ------ This page summarizes the '''present instrumentation''' installed at the 30m observatory. <
> The current system '''status''' is described [[http://www.iram.es/IRAMES/mainWiki/TelescopeSystemStatus|on a second page]] <> == Frontends == === Heterodyne Receivers === * EmirforAstronomers : '''new''' EMIR (Eight MIxer Receiver) * HeraforAstronomers : HERA 3x3 dual-polarisation 1mm receiver * AbcdforAstronomers : '''old''' ABCD receivers * [[http://www.iram.es/IRAMES/groups/receiver/receiver.html|Web pages of the IRAM/Granada receiver group]] === Bolometers === Two large field bolometer cameras are installed: '''MAMBO1''' with 37 pixels, and '''MAMBO2''' with 117 pixels ([[http://www.mpifr-bonn.mpg.de/div/bolometer/#mamgo|MAx-Planck Millimeter BOlometer Array]]). Usually MAMBO2 is in use. Both cameras work at 1.2mm wavelength, the HPBW is 11", pixel spacing is 20", and the sensitivity is 1.5mJy. This is the rms after 10 minutes integration (normal bolometric conditions) with skynoise removal. See [[http://www.iram.es/IRAMES/mainWiki/MamboWebPage|the MAMBO page for details.]] [[#beginOfPage|Back to top]] == Telescope efficiencies and beam widths == Iram30mEfficiencies == Backends == * Backends for the new EMIR receiver, HERA, and MAMBO: BackendsForEmirHeraMambo * Backends for the old ABCD receivers (till mid March 2009): BackendsForAbcdReceivers [[#beginOfPage|Back to top]] == Control System == The 30-m telescope runs under the New Control System (NCS), see: . [[http://www.iram.es/IRAMES/ncs30m/|NCS documentation]] [[http://mrt-lx1/mainWiki/|Wiki with up-to-date Notes on NCS]] Observing modes and source offsets in: * Projection "Radio" (same offsets as in old CS) in Equatorial J2000.0 * "true angle" horizontal * Nasmyth (receiver offsets) [[#beginOfPage|Back to top]] == Observing Modes and Switching Modes == || Observing mode || swTotal || swBeam || swWobbler || swFrequency || || '''Calibrate''' (Heterodyne) || X || || || || || '''Pointing''' || X || X || X || || || '''Focus''' || X || X || X || || || '''Tip''' (Skydip) || X || || || || || '''Track''' || || || || fsw || || '''ONOFF''' || psw || || wsw || || || '''OTFMAP''' (Heterodyne) || otf/psw || || || otf/fsw || || '''Raster''' || || || || || || '''OTFMAP''' (MAMBO Bolometer) || || || X || || || '''VLBI''' || X || || || || * for more details on observing and switching modes, see the section "NCS explained" in the [[http://www.iram.es/IRAMES/documents/ncs30mPako/Current/PDF/pako.pdf|pako cookbook]] * '''swTotal''' stands for total power observations without switching, while still using the internal synchronization signals. * '''swBeam''' beam switched observations using the chopper wheel on mirror M4. * '''swWobbler''' switching the wobbling secondary (M2). The maximum allowed throw is +/-2'. * '''swFrequency''' switching the local oscillator frequency * '''Pointing''': Using nearby (within 10 degree) pointing sources, <1" accuracy can be obtained; with absolute ("blind") pointing, the accuracy is about 2" rms, the receivers are aligned within 1.7" (see the [[http://www.iram.es/IRAMES/mainWiki/TelescopeSystemStatus|Telescope Status page]] for current values). Checking the pointing and alignment (using e.g. a planet) is the responsibility of the observer. * '''Focus''': residual errors of <1mm may need correction. There are systematic differences of upto 0.6mm in the focus of the different receivers (cf. [[http://www.iram.es/IRAMES/mainWiki/TelescopeSystemStatus|Telescope Status page]]). The focus is subject to change especially during sunrise and sunset. * '''Position switching (psw)''': the combination of ONOFF with swTotal is called "Position Switching". Only relative off-source reference positions are possible. * '''Wobbler switching (wsw)''': often called '''double beam switching mode''': max. 240" throw at 0.25 Hz, standard phase duration 0.5 Hz. * '''Frequency switching (fsw)''': max. 45 km/s throw up to about 10 Hz. * '''On the fly mapping (Heterodyne)''': Works with all receivers and backends, typical dump rate 0.5 to 10 Hz. ''OTF can be observed without reference position, e.g. for galaxies, and MIRA is able to use emission-free OTF data as reference!'' * '''Raster mapping''' is at present '''not offered'''. The observer may want to use either psw or otf instead. * '''Polarimetry''': using VESPA as an IF polarimeter [[#beginOfPage|Back to top]] == Weather station and Taumeter == * [[http://mrt-lx3.iram.es/tau/meteo-main.php|Weather station]] *Wind velocity and direction measured on hill behind the telescope * Outside temperature and relative humidity measured at base of telescope. In case the sensors are frozen, the operator will use a mobile weather station and enter values by hand into the drive program. * Pressure measured at entrance to control building * [[http://mrt-lx3.iram.es/tau/taumeter-main-db.php|Taumeter]] does regular skydips to inform the observer about the sky transmission near '''225 GHz'''. The local oscillator works at 225GHz. The IF is 1.5GHz and the bandwidth is 0.5GHz. It is a double-sideband Schottky receiver. [[#beginOfPage|Back to top]] Old [[http://www.iram.es/IRAMES/telescope/telescopeSummary/telescope_summary.html|Telescope System Summary page of September 07]] This is page http://www.iram.es/IRAMES/mainWiki/TelescopeSystemSummary moderated by Carsten Kramer