This site requires javascript to be enabled to fuction correctly


Knowledgebase : General ALMA Queries
Raw ALMA data files include autocorrelation outputs from the antennas which do not have atmospheric or instrumental effects subtracted. In principle, a well-modeled astronomical source could be subtracted from the autocorrelations, leaving the atmospheric...
A new feature that has been requested from the users has finally come to the helpdesk! You can now reply to your open tickets via email. When you get a notification of a reply to your helpdesk ticket, you can now hit reply in your email client instead o...
Yes! you can submit a ticket to EA ARC in Japanese. EA ARC では日本語のチケットも受け付けます。日本語での質問・要望に対しては、原則として日本語で回答します。 ただし、プロポーザル締め切り直前に行われる24時間体制のEmergency Proposal Submission Dep. では英語のみのサポートとなります(通常のCycleのプロポーザルでは締め切り72時間前からEmergency Proposal Submission Dep.となり...
A statement on the potential for publicity for an ALMA proposal is no longer required. However, as stated in ALMA Proposers Guide in the Documents and Tools [https://www.almascience.org/documents-and-tools] Section of the ALMA Science Portal [http://almas...
There is no difference in the feathering process between the Solar and other observations, except for the case that the field of view is very near the solar limb (< the diameter of the primary beam). For the limb observations, you might need to apply the ...
For a full description of the ALMA scheduling process, see the ALMA Proposers Guide in the Documents and Tools [https://www.almascience.org/documents-and-tools] Section of the ALMA Science Portal [http://almascience.org/]. Proposals will be assessed on ...
The ALMA calibrator database can be directly queried through a web form at http://almascience.org/sc/ [http://almascience.org/sc/]. Alternatively, you can query the ALMA calibrator database from the OT in this way: * Open up the OT and create a Scie...
A principal investigator (PI) and people delegated by the PI (see Knowledgebase Article: _"As PI of an ALMA proposal, how can I give others access to the data during the proprietary period?_ [https://help.almascience.org/index.php?/Knowledgebase/Article/V...
ALMA can actually point at the Sun (solar observations are available from Cycle 4). Small grooves or etchings in the antenna surface are designed to ensure that sunlight is not reflected to the secondary subreflector. However, detectable solar emission is...
Please note first the limitations of ALMA observations: * The longest duration of one scheduling block (SB) is 2 hours. * Every SB includes a calibration session before starting scientific observation. The duration of the session is 25~30 minutes. ...
The ALMA Science Portal allows users to link their ALMA accounts to an account at a trusted institution. This can be done on the Science Portal profile page [https://asa.alma.cl/UserRegistration//secure/updateAccount.jsp], by clicking on the "Account link...
You can use the OT to retrieve your current and any previously submitted ALMA proposals that you are PI or Co-I on. Use the OT commands: File=>Open Project=>From Archive, and search based on your ALMA username or proposal ID. If your username and passwo...
The ALMA Snooping Project Interface (SnooPI) is a read-only web application that allows Principal Investigators (PIs) to follow their ALMA projects from the moment of acceptance all the way to data delivery. SnooPI is available at http://almascience.org/o...
When you request an observation with single-pointing, the time cadence of images is limited by the integration time of the 64-bits correlator. Since the integration time is set to 1 second, the highest time cadence is 1 second. When you request a "mosaic"...
For interferometric observations, we have to observe a quasar as a phase calibrator every ~10 minutes for single-pointing, ~5 minuets for MOSAIC observations at Bands 3 and 6. Therefore, the duration of a continuous solar observation is approximately 10 o...
For sources distributed widely in the sky, the Science Goal (SG) will be split by the OT into different "clusters", each grouping all sources within 10 degrees. WHILE THERE IS NO RESTRICTION ON THE TOTAL NUMBER OF SOURCES IN A SG, FOR EACH GROUPING ...
For interferometric observations, the highest time resolution is set by the shortest correlator dump time. In so-called time division mode (TDM), the correlator can output every 16ms (though at reduced spectral resolution), so you can Nyquist sample a 32m...
If not completed by the end of the Cycle, previous Cycle observing programs assigned grade A will be carried over to the following Cycle. The relative scheduling priority ranking of programs will proceed as follows (see the ALMA Proposers Guide in the D...
The order ALMA is hoping to add new bands is as follows: * Band 1 receivers (35--50 GHz) are currently being developed as an ALMA Development Project. * Prototype receivers for Band 2 (67--90 GHz or more) are currently under development.
After ALMA data are fully assessed for quality assurance and delivered through the Regional ARCs, the one year (6 months for a DDT) proprietary clock starts for that delivered MOUS.  Extensions to the proprietary period for any observing program are _stro...
Yes. Submitted project proposals may include principal investigators (PIs) and co-investigators (Co-Is) who are not affiliated with any of the three ALMA Executive regions.
If a user selects the "Choose a Solar System Object" option (SSO) in the OT Field Setup, the OT sets the position to RA=0deg, Dec=0deg. However the OT time estimate depends on the declination of the observed source, as described in Section "Sky temperat...
Eight observing bands are currently available observations. They are designated bands 3, 4, 5, 6, 7, 8, 9 and 10. The nominal frequency & wavelength ranges are:   Band Frequency Range Wavelength Range   (GHz) (mm) 3 84-116 ...
The ALMA duplication guidelines are published at http://almascience.org/proposing/call-for-proposals/duplications [http://almascience.org/proposing/call-for-proposals/duplications], the duplication criteria are published in the Duplicate Observation and R...
When you submit a helpdesk ticket, notification is sent to triage staff at your affiliated ALMA Regional Center (ARC). Triage staff will assign the ticket to the appropriate staff person within the ARC and a reply will be sent within two working days. 7...
Large Programs may designate any number of co-PIs, who share the overall responsibility with the PI in conducting the proposed science, however only the PI has the responsibility for SBs preparation and approval, and the delivery of the data products in a...
http://almascience.org/alma-data/publication-acknowledgement [http://almascience.org/alma-data/publication-acknowledgement] Publications making use of ALMA data must include the following statement in the acknowledgment: “This paper makes use of the f...
The absolute positional accuracy of an ALMA image, made with normal phase referencing depends, on the target signal to noise and the array resolution, but also on the quality of the phase calibration that depends on the atmosphere delay fluctuations and t...
The Atacama Compact Array (ACA), also known as the Morita Array, is composed of twelve closely spaced 7-meter antennas (7-m Array), and four 12-meter antennas for single dish observations (Total Power Array). The array is designed to enhance wide-field im...
If you have CASA information, tips, or tricks to share with the ALMA or CASA communities please submit it to the NRAO Science Forum. This could include tips on using CASA, scripts or modules that extend CASA's functionality, questions about installing CAS...
The bandpass stability has been tested during 2013 and 2014 for Bands 3, 4, 6, 7, 8, 9, and 10 with 21–35 antennas. The amplitude variation is estimated to be <0.1% for Bands 3, 4, and 6, and <1% for the other Bands. The phase variation is estimated to be...
The voltage pattern assumed by CASA for the ALMA 12-m primary beam is currently hard coded to a uniformly illuminated 10.7-m dish with 0.75m blockage, resulting in an Airy disk whose FWHM is SIMILAR to a 12m Gaussian illumination with -12dB taper and 0.75...
An ephemeris file gives the RA and DEC as a function of time. All positions should be in ICRS (J2000) The ephemeris file should cover the entire potential time span of the project (up to the entire Cycle), and may have up to ~90,000 entries.  The PI sho...
The spectral resolution of ALMA data will be two times the channel spacing, as the data will be Hanning smoothed by default, when no channel averaging is set in the Observing Tool (OT) by the proposers. The OT reports the number of Hanning-smoothed spectr...
Users of any professional background, nationality or affiliation may submit an ALMA proposal. All proposals are reviewed without regard to the nationalities or affiliations of the investigators. Successful projects will have their observing time assigne...
The selection process for projects is explained in ALMA Proposer's Guide available at the Documents and Tools [http://almascience.org/documents-and-tools/] Section of the ALMA Science Portal [http://almascience.org/]. Proposals will be assessed on the ove...
The ALMA Regional Center (ARC) websites are: Europe: http://www.eso.org/sci/facilities/alma/arc.html [http://www.eso.org/sci/facilities/alma/arc.html] North America: https://science.nrao.edu/facilities/alma [https://science.nrao.edu/facilities/alma]...
The details of the Atacama Compact Array (ACA) are found in the ALMA Technical Handbook [http://almascience.org/documents-and-tools/latest/alma-technical-handbook]. Related Knowledgebase article: * "What is the Atacama Compact Array (ACA)?" [https:/...
For ALMA Cycles 0-4 data packages, the images that are included in the data delivery package may not include all spectral windows, or all channels, or all targets that were observed as part of the science program. These images are meant to be representati...