NIKA2 Homepage

The New IRAM KID Array 2 (NIKA2) is a dual-band camera operating with three frequency-multiplexed kilopixels arrays of Lumped Element Kinetic Inductance Detectors (LEKID) cooled at 150mK. NIKA2 is designed to observe the intensity and polarisation of the sky at 1.15 and 2.0 mm. NIKA2 was successfully installed in October 2015. Commissioning is ongoing. NIKA2 will become an IRAM resident instrument for the next ten years or more. NIKA2 is built by an international consortium, led by the Institute Neel (Grenoble France).

NIKA2 in the web:

• NIKA2 website at IPAG

• NIKA2-internal wiki at IRAM-FR.

Overview

Some prelimiary characteristics of NIKA-2:

Comments: A new 2mm array with 616 pixels was installed mid September 2016. The previously installed array had 1020 pixels. Further changes in September 2016 were a new dichroic frequency splitter, new lenses and a new cryostat window. In addition, several of the 20 readout electronics boards have been replaced with the last version. NIKA2 now has a homogeneous set of boards, plus several spare boards. Commissioning will continue at least till February 2017. It is planned to start science observations later in the winter semester.

Call for proposals and time estimator

In the upcoming summer semester running from 1 June to 30 November 2017, a limited amount of time will be available for NIKA2 science projects. See the call for proposals. On the following page, we give information on how to estimate total observing times:

• Guidelines to estimate observing times for summer semester 2017.

Open Time Programs

List of open time projects accepted to be observed with NIKA2 at the 30m telescope.

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Guaranteed Time Programs

Four Large Programs for NIKA2 in guaranteed time were submitted to the Program Committee for the deadline in September 2016. All four have been rated high by the PC and will be observed. Here, we provide the proposal abstracts together with the list of sources and map sizes. These shall be "fenced" against new continuum 2mm/1mm mapping projects at the 30m or NOEMA. <18-January 2017>

Abstracts

Galactic Star Formation with NIKA2 - GASTON (122-16)

Abstract: The IMF is a fundamental global output of the star formation process, and the question of its origin and universality has been a long-standing open issue. While the base of the IMF (0.1 to 1 Msun) may result from Jeans-like fragmentation of interstellar filaments, the problem of how the most extreme stellar objects (brown dwarfs, intermediate- and high-mass stars) build up their masses remains unsettled. The high-sensitivity and fast mapping capability of the NIKA2 camera offer the unique opportunity to detect large populations of low-brightness sources, and probe star-forming regions as never before. We propose to use this new instrument to: i. perform a complete survey of pre-brown-dwarf cores in two nearby star-forming regions, ii. map the intertwined populations of interstellar filaments and intermediate to high-mass cores within rich galactic plane star-forming regions; iii. use the dual band capability of NIKA2 at 1.2mm and 2mm to constrain the dust properties in a broad range of environments and reduce mass uncertainties by a factor of 3. Altogether, these observations will provide new insight on the earliest stages of star formation across both ends of the stellar IMF.

PI is Nicolas Peretto.

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Interpreting the Millimetre Emission of Galaxies with IRAM and NIKA (IMEGIN) (160-16)

Abstract: The mm part of the spectrum is one of the least explored parts of a galaxy’s spectral energy distribution (SED), yet it contains emission from three fundamentally important physical processes. These processes are thermal emission from dust, free-free emission from ionized gas and synchrotron emission from charged particles moving in the galactic magnetic field. We are proposing to use the NIKA2 camera to observe a sample of 22 nearby galaxies that also have considerable ancillary data across the SED from the radio to the ultra-violet. We will investigate the dust emissivity, the relationship between the three physical processes and their relation to star formation and the gas-to-dust ratio. As the sample galaxies are of large angular size we will be able to carry out this project in a spatially resolved way and hence investigate the different environments found within galaxies.

PI is Jonathan Davies

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The NIKA2 Cosmological Legacy Survey (N2CLS) (192-16)

Abstract: Using 300h of the NIKA2 Guaranteed Time, we will map the star formation at high redshift in two of the most popular fields. N2CLS will reach for the first time the confusion noise at the 30m, in 160 square arcminutes in GOODS-N. In COSMOS, N2CLS sensitivity will at least match or outperform the sensitivity of the S2CLS survey at 850 microns on 0.5 square degree. N2CLS will detect hundreds of dust-obscured optically-faint galaxies during their major episodes of formation in the early universe. It will fully open a new window on the faint and high-redshift dusty Universe and answer the outstanding issue of whether dusty star-formation contributes to early galaxy evolution. It will uniquely probe the transition at z~3-4 of the cosmic star-formation history between the predominantly unobscured growth in the early Universe and the obscured star formation, driven by the build-up of the most massive galaxies during the peak of cosmic assembly. The availability of this uniquely large sample of mm-selected galaxies with superb supporting multi-wavelength data will provide the opportunity to address the history of star formation, dust production and the growth of large-scale structures.

PIs: Guilaine Lagache, Alexandre Beelen, Nicolas Ponthieu

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High-resolution tSZ observations of a large sample of clusters of galaxies (NIKA2SZ) (199-16)

Abstract: The development of precision cosmology with clusters of galaxies requires high angular resolution observations to extend the understanding of galaxy clusters towards high redshift. The NIKA2 camera at the IRAM 30 m telescope is the only instrument currently in operation that is suited for this kind of observations, given its resolution, sensitivity and dual-band observation capability. We intend to observe a large sample of clusters of galaxies at high redshift (0.5 < z < 0.9), selected from the Planck and ACT catalogs. We have formed a representative cluster sample for redshift evolution and cosmological studies, with a homogeneous coverage in cluster mass as reconstructed from the integrated Compton parameter. We will use the SZ-dedicated pipeline that we have developed for the SZ observation with the NIKA camera. Our primary objective is to produce unprecedented high-quality deliverables (tSZ maps and pressure profiles) for all clusters of the sample. NIKA2 data will be complemented with ancillary data including X-ray, optical and radio observations. The full dataset will lead to significant improvements on the use of clusters of galaxies to draw cosmological constraints.

PIs: Frédéric Mayet, Barbara Comis

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Source list

• NIKA2-GT-LPs-18jan2017.pdf

• NIKA2-GT-LPs-18jan2017.xls

Publications

• Instrument/detectors papers:

  • Bourrion et al. 2016, NIKEL_AMC: Readout electronics for the NIKA2 experiment, arxiv

  • Catalano et al. 2016, The NIKA2 commissioning campaign: performance and first results, arxiv

  • Calvo et al. 2016, The NIKA2 instrument, a dual-band kilopixel KID array for millimetric astronomy, arxiv

  • Goupy et al. 2016, Microfabrication technology for large LEKID arrays : from NIKA2 to future applications, arxiv

  • Monfardini et al. 2014, Latest NIKA Results and the NIKA-2 Project, JLTP 176, 787, arxiv

  • Catalano et al. 2014, Performance and calibration of the NIKA camera at the IRAM 30 m telescope, A&A 569, A9, arxiv

  • Calvo et al. 2013, Improved mm-wave photometry for kinetic inductance detectors, A&A, 551, L12 ADS

  • Bourrion et al. 2012, NIKEL: Electronics and data acquisition for kilopixels kinetic inductance camera, Journal of Instrumentation, 7, 07, pp. 7014. arXiv

  • Monfardini et al. 2011, A Dual-band Millimeter-wave Kinetic Inductance Camera for the IRAM 30 m Telescope, ApJS, 194, 2, article id. 24. arXiv

  • Internal list of technical papers

• Astronomical papers:

  • Ritacco, A., Ponthieu, N, Catalano, A., et al, 2017, Polarimetry at millimeter wavelengths with the NIKA camera: calibration and performance, A&A 599, A34, ADS

  • Ruppin, F., Adam, R., Comis, B., et al. 2016, Non parametric deprojection of NIKA SZ observations: pressure distribution in the Planck-discovered cluster PSZ1 G045.85+57.71, A&A, in press ADS

  • Adam, R., Bartalucci, I., Pratt, G. W., et al. 2016, Mapping the kinetic Sunyaev-Zel'dovich effect toward MACS J0717.5+3745 with NIKA, A&A, in press ADS

  • Adam, R., Comis, B., Bartalucci, I., et al. 2016, High angular resolution Sunyaev-Zel'dovich observations of MACS J1423.8+2404 with NIKA: Multiwavelength analysis, A&A, 586, 122 ADS

  • Adam, R., Comis, B., Macias-Perez, J.-F., et al, 2015, Pressure distribution of the high-redshift cluster of galaxies CL J1226.9+3332 with NIKA, A&A, 576, A12 ADS

  • Adam, R., Comis, B., Macias-Perez, J.-F, et al, 2014, First observation of the thermal Sunyaev-Zel'dovich effect with kinetic inductance detectors, A&A, 569, 66 ADS

• Ph.D. thesis:

  • Rémi Adam (2012-2015) - Advisors: J.F. Macías-Pérez and F.X. Désert (Observation des amas de galaxies par effet Sunyaev-Zel'dovich et de la polarisation du fond diffus cosmologique : de Planck à NIKA (in French))

  • Alessia Ritacco (2013-2016) - Advisors: J.F. Macías-Pérez, Alessandro Monfardini, Andrea Catalano, Nicolas Ponthieu (Polarimetry at millimeter wavelengths with the instruments NIKA and NIKA2)

• Talks:

  • Alessia Ritacco, November 2016, Polarimetry at Millimeter wavelengths with NIKA and NIKA2 ritacco-seminar-nika2-nov2016.pdf

• NIKA2 publications list maintained at IPAG

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Technical Documentation

• NIKA2 Data Acquisition, Camadia, M.Calvo, Feb-2016

• NIKA2 tuning procedure and data flagging description, M.Calvo, Feb-2016

• Instrument-related documentation page

• Wiki-pages:

  • Discussion on beams

  • Spectral bands

  • Remote network access to nika2-a computer

  • Pool observations provides information on the observing modes offered for NIKA2 and examples of the scripts that you must prepare to observe your project.

  • Observing session provides an example of a typical session with NIKA2 at the 30m telescope.

  • Pointing sources and calibrators provides a list of pointing sources and calibrators.

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Technical runs to commission NIKA2

• 1^st test run of NIKA2: 29-October-2015 till 10-November-2015. Installation, cool down at the 30m, testing/debugging/developing. [= Run 13 of a NIKA instrument]

  • Go to the 1st run Wiki page

  • Private Wiki detailing the organization of the run and the instrument characterization plan

• 2^nd test run of NIKA2: 24-November-2015 till 02-December-2015. Continue tests started during run 1, in particular Beam maps and NEFD with the 13 NIKEL boards assembled the last days of run 1. [= Run 14 of a NIKA instrument]

  • Go to the 2nd run Wiki page

• 3^rd test run of NIKA2: 12-January-2016 till 01-February-2016. Implementation of new NIKEL boards; the 20 data lines of NIKA2 are foreseen to be plugged simultaneously. With the 3 arrays fully read, continue and redo tests started with runs 1 & 2, in particular Beam maps and NEFD. [= Run 15 of a NIKA instrument]

  • Go to the 3rd run Wiki page

• 4^th test run of NIKA2: 1-March-2016 till 15-March-2016. Continue tests started with previous runs, in particular investigate deeper beam patterns (XY focus, beam maps), synchronization, array 1 & 3 performances vs electronic boards, NEFD, mapping strategies. [= Run 16 of a NIKA instrument]

  • Go to the 4th run Wiki page

• Dark run: 4-May-2016. Test sensitivity of NIKA2 to external electromagnetic perturbations, with the entrance window of the cryostat closed. [= Run 17 of a NIKA instrument]

• 5^th test run of NIKA2: 16-September-2016 till 11-October-2016. Upgrade NIKA2 with new dichroic, new corrugated lenses and window, new 2mm array, new NIKEL boards (get the 20 lines with homogeneous electronics, v3); redo better the tests started with previous runs (mostly beam maps in best weather conditions, but also various types of scan to investigate deeper beams and noise, synchronization, NEFD, skydips, mapping strategies, possibly polarization. [= Run 18 of a NIKA instrument]

  • Go to the 5th run Wiki page

• 6^th test run of NIKA2: 25-October-2016 till 1-November-2016. Continue NIKA2 commissioning. [= Run 19 of a NIKA instrument]

  • Go to the 6th run Wiki page

• 7^th test run of NIKA2: 6-December-2016 till 13-December-2016. Test DRO based external calibrator, continue NIKA2 commissioning. [= Run 20 of a NIKA instrument]

  • Go to the 7th run Wiki page

• 8^th test run of NIKA2: 9-January-2017 to 13-January-2017, then 23-January to 27-January. Reverse array 1 lens to smooth version, short test on sky to see effect of the intervention. [= Run 21 of a NIKA instrument]

  • Go to the 8th run Wiki page

• 9^th test run of NIKA2: 21-February-2017 to 28-February-2017. Resume NIKA2 commissioning after run 8 intervention. [= Run 22 of a NIKA instrument]

  • Go to the 9th run Wiki page

• 10^th test run of NIKA2: 18-April-2017 to 25-April-2017. End of commissioning phase 1, science verification. [= Run 23 of a NIKA instrument]

  • Go to the 10th run Wiki page

Support teams

• Overall coordinator:

  • Samuel Leclercq (IRAM/Grenoble, <leclercq@iram.fr>)

• NIKA2 team:

  • Alessandro Monfardini <monfardini@neel.cnrs.fr> (PI, IN)

  • Alain Benoit <alain.benoit@grenoble.cnrs.fr>

  • François-Xavier Désert <francois-xavier.desert@univ-grenoble-alpes.fr> (IPAG)

  • Martino Calvo <martino.calvo@neel.cnrs.fr> (IN)

  • Johannes Goupy <johannes.goupy@neel.cnrs.fr> (IN)

  • Nicolas Ponthieu <nicolas.ponthieu@univ-grenoble-alpes.fr> (IPAG)

  • Juan Macias-Perez <macias@lpsc.in2p3.fr> (LPSC)

  • Andrea Catalano <catalano@lpsc.in2p3.fr> (LPSC)

  • Laurence Perotto <laurence.perotto@lpsc.in2p3.fr> (LPSC)

• IRAM/Granada NIKA2 support team:

  • Carsten Kramer (Station Manager and Scheduler, <kramer@iram.es>)

  • Pablo Garcia (time estimator, continuum Pool Manager, <pgarcia@iram.es>)

  • Albrecht Sievers (IMBfits, <sievers@iram.es>)

  • Hans Ungerechts (NCS/pako, <ungerechts@iram.es>)

  • Pablo Mellado (Computers/Network, <mellado@iram.es>)

  • Alessia Ritacco (astronomers assistance, commissioning support, <ritaccoa@iram.es>)

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Created : 2015.AUG.05 by Israel Hermelo, Last update : 2017.FEB.06, by Pablo García (PG). This page is maintained by PG, CK, SL and the NIKA team.