Gaia EDR3 Passbands

 

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Gaia EDR3 passbands as produced by Coordination Unit 5 of the Gaia Data Processing and Analysis Consortium. The coloured lines in the figure show the G, GBP and GRP passbands (green: G; blue: GBP; red: GRP), defining the Gaia EDR3 photometric system. The thin, grey lines show the nominal, pre-launch passbands published in Jordi et al. 2010, used for Gaia DR1.​​​​​​​ Credits: ESA/Gaia/DPAC, P. Montegriffo, F. De Angeli, M. Bellazzini, E. Pancino, C. Cacciari, D. W. Evans, and CU5/PhotPipe team.

 

Due to the complexity and extraordinary accuracy of Gaia photometric measurements, the calibration of most instrumental effects needs to rely uniquely on internal data. This generates a photometric system corresponding to an average instrument that needs to be linked to the absolute system via an ad hoc calibration. This fundamental step in the Gaia data processing is referred to as the photometric external calibration.

It is important to understand that due to the cyclic processing of the Gaia data leading to the publication of better and more complete releases, the internal average instrument generated at each cycle is different. This implies that any comparison of passbands derived for different releases is meaningless.

The result of the photometric external calibration is the definition of a set of passbands (one per band or instrument G, G_BP and G_RP) that describe the combined effect of filter (and prisms in the Gaia BP/RP case), transmission, optical path and detector quantum efficiency as a function of wavelength and additional features introduced by the processing of the data. Once the passband is available, zero points converting internal fluxes to absolute magnitudes can be derived and it becomes possible to generate synthetic photometry in the Gaia photometric system from any known SED (either modelled or measured with other instruments).

In principle, by comparing the observed photometry of an arbitrarily large set of sources with well-known spectral energy distributions (SEDs) with the synthetic photometry obtained assuming some mathematical model for the passband, it should be possible to infer the true shape of the passband. However, in practice, any such set of spectrophotometric calibrators will only represent a subspace of all possible SED shapes because of its limited size but mostly because there are classes of astrophysical objects that are intrinsically variable and hence cannot be used as calibrators. This implies that only a subset of model components are constrained by such set of calibrators leaving others completely unconstrained (Weiler 2018). This limitation affected the determination of the Gaia DR2 passbands that relied uniquely on the set of Spectro-Photometric Standard Sources (SPSS, Pancino et al. 2012, Altavilla et al. 2015, Marinoni et al. 2016) as calibrators. As a result, several sets of passbands were produced using different sets of calibrators: two different sets in Evans et al. (2018), others in Weiler (2018) and Maíz Apellániz & Weiler (2018), all providing minimal changes in the SPSS residuals between observed and synthetic photometry.

To mitigate this limitation, for Gaia EDR3 a much larger set of auxiliary calibrators (approximately 100K) covering a wide range in stellar types was employed to firmly tie the photometric external calibration to the BP/RP spectra. These were converted to the absolute system to provide SEDs for the large set of auxiliary calibrators. The external calibration of the BP/RP spectral data was still based mostly on the SPSS data thus ensuring a solid absolute flux scale, but also relied on other types of sources, featuring strong emission lines in the BP/RP spectral range, to further constrain most model components. A more comprehensive description of the photometric and spectral external calibrations will be published in Riello et al. (2020, the paper presenting the EDR3 photometry) and Montegriffo et al. (in preparation, a paper entirely dedicated to the external calibration of the BP/RP spectra). The passbands are shown in the figure above as green, blue, and red solid lines for the G, G_BP, and G_RP bands, respectively. The thin grey lines show the nominal, pre-launch passbands published in Jordi et al. 2010.

The following link provides access to the Gaia EDR3 passband data:

 

Download here the Gaia EDR3 passbands and zero points

 

The Gaia EDR3 passband data has been provided to you by Coordination Unit 5 of the Gaia Data Processing and Analysis Consortium. Please realise that small corrections might still be added to the README document. With the release of Gaia EDR3 on 3 December 2020, also the processing papers and the data release documentation will be published. These should be considered from then onwards the most important reference information for the Gaia EDR3 passbands data.

 

 

Credits: ESA/Gaia/DPAC, P. Montegriffo, F. De Angeli, M. Bellazzini, E. Pancino, C. Cacciari, D. W. Evans, and CU5/PhotPipe team

​​​​​​​[Published: 29 October 2020]

Image of the Week Archive

2020
29/10: Gaia EDR3 passbands
15/10: Star clusters are only the tip of the iceberg
04/09: Discovery of a year long superoutburst in a white dwarf binary
12/08: First calibrated XP spectra
22/07: Gaia and the size of the Solar System
16/07: Testing CDM and geometry-driven Milky Way rotation Curve Models
30/06: Gaia's impact on Solar system science
14/05: Machine-learning techniques reveal hundreds of open clusters in Gaia data
20/03: The chemical trace of Galactic stellar populations as seen by Gaia
09/01: Discovery of a new star cluster: Price-Whelan1
08/01: Largest ever seen gaseous structure in our Galaxy
2019
20/12: The lost stars of the Hyades
06/12: Do we see a dark-matter like effect in globular clusters?
12/11: Hypervelocity star ejected from a supermassive black hole
17/09: Instrument Development Award
08/08: 30th anniversary of Hipparcos
17/07: Whitehead Eclipse Avoidance Manoeuvre
28/06: Following up on Gaia Solar System Objects
19/06: News from the Gaia Archive
29/05: Spectroscopic variability of emission lines stars with Gaia
24/05: Evidence of new magnetic transitions in late-type stars
03/05: Atmospheric dynamics of AGB stars revealed by Gaia
25/04: Geographic contributions to DPAC
22/04: omega Centauri's lost stars
18/04: 53rd ESLAB symposium "the Gaia universe"
18/02: A river of stars
2018
21/12: Sonification of Gaia data
18/12: Gaia captures a rare FU Ori outburst
12/12: Changes in the DPAC Executive
26/11:New Very Low Mass dwarfs in Gaia data
19/11: Hypervelocity White Dwarfs in Gaia data
15/11: Hunting evolved carbon stars with Gaia RP spectra
13/11: Gaia catches the movement of the tiny galaxies surrounding the Milky Way
06/11: Secrets of the "wild duck" cluster revealed
12/10: 25 years since the initial GAIA proposal
09/10: 3rd Gaia DPAC Consortium Meeting
30/09: A new panoramic sky map of the Milky Way's Stellar Streams
25/09: Plausible home stars for interstellar object 'Oumuamua
11/09: Impressions from the IAU General Assembly
30/06: Asteroids in Gaia Data
14/06: Mapping and visualising Gaia DR2

25/04: In-depth stories on Gaia DR2

14/04: Gaia tops one trillion observations
16/03: Gaia DR2 Passbands
27/02: Triton observation campaign
11/02: Gaia Women In Science
29/01: Following-up on Gaia
2017
19/12: 4th launch anniversary
24/11: Gaia-GOSA service
27/10: German Gaia stamp in the making
19/10: Hertzsprung-russell diagram using Gaia DR1
05/10: Updated prediction to the Triton occultation campaign
04/10: 1:1 Gaia model arrives at ESAC
31/08: Close stellar encounters from the first Gaia data release
16/08: Preliminary view of the Gaia sky in colour
07/07: Chariklo stellar occultation follow-up
24/04: Gaia reveals the composition of asteroids
20/04: Extra-galactic observations with Gaia
10/04: How faint are the faintest Gaia stars?
24/03: Pulsating stars to study Galactic structures
09/02: Known exoplanetary transits in Gaia data
31/01: Successful second DPAC Consortium Meeting
2016
23/12: Interactive and statistical visualisation of Gaia DR1 with vaex
16/12: Standard uncertainties for the photometric data (in GDR1)
25/11: Signature of the rotation of the galactic bar uncovered
15/11: Successful first DR1 Workshop
27/10: Microlensing Follow-Up
21/10: Asteroid Occultation
16/09: First DR1 results
14/09: Pluto Stellar Occultation
15/06: Happy Birthday, DPAC!
10/06: 1000th run of the Initial Data Treatment system
04/05: Complementing Gaia observations of the densest sky regions
22/04: A window to Gaia - the focal plane
05/04: Hipparcos interactive data access tool
24/03: Gaia spots a sunspot
29/02: Gaia sees exploding stars next door
11/02: A new heart for the Gaia Object Generator
04/02: Searching for solar siblings with Gaia
28/01: Globular cluster colour-magnitude diagrams
21/01: Gaia resolving power estimated with Pluto and Charon
12/01: 100th First-Look Weekly Report
06/01: Gaia intersects a Perseid meteoroid
2015
18/12: Tales of two clusters retold by Gaia
11/11: Lunar transit temperature plots
06/11: Gaia's sensors scan a lunar transit
03/11: Celebrity comet spotted among Gaia's stars
09/10: The SB2 stars as seen by Gaia's RVS
02/10: The colour of Gaia's eyes
24/09: Estimating distances from parallaxes
18/09: Gaia orbit reconstruction
31/07: Asteroids all around
17/07: Gaia satellite and amateur astronomers spot one in a billion star
03/07: Counting stars with Gaia
01/07: Avionics Model test bench arrives at ESOC
28/05: Short period/faint magnitude Cepheids in the Large Magellanic Cloud
19/05: Visualising Gaia Photometric Science Alerts
09/04: Gaia honours Einstein by observing his cross
02/04: 1 April - First Look Scientists play practical joke
05/03: RR Lyrae stars in the Large Magellanic Cloud as seen by Gaia
26/02: First Gaia BP/RP deblended spectra
19/02: 13 months of GBOT Gaia observations
12/02: Added Value Interface Portal for Gaia
04/02: Gaia's potential for the discovery of circumbinary planets
26/01: DIBs in three hot stars as seen by Gaia's RVS
15/01: The Tycho-Gaia Astrometric Solution
06/01: Close encounters of the stellar kind
2014
12/12: Gaia detects microlensing event
05/12: Cat's Eye Nebula as seen by Gaia
01/12: BFOSC observation of Gaia at L2
24/11: Gaia spectra of six stars
13/11: Omega Centauri as seen by Gaia
02/10: RVS Data Processing
12/09: Gaia discovers first supernova
04/08: Gaia flag arrives at ESAC
29/07: Gaia handover
15/07: Eclipsing binaries
03/07: Asteroids at the "photo finish"
19/06: Calibration image III - Messier 51
05/06: First Gaia BP/RP and RVS spectra
02/06: Sky coverage of Gaia during commissioning
03/04: Gaia source detection
21/02: Sky-background false detections in the sky mapper
14/02: Gaia calibration images II
06/02: Gaia calibration image I
28/01: Gaia telescope light path
17/01: First star shines for Gaia
14/01: Radiation Campaign #4
06/01: Asteroid detection by Gaia
2013
17/12: Gaia in the gantry
12/12: The sky in G magnitude
05/12: Pre-launch release of spectrophotometric standard stars
28/11: From one to one billion pixels
21/11: The Hipparcos all-sky map
15/10: Gaia Sunshield Deployment Test
08/10: Initial Gaia Source List
17/09: CU1 Operations Workshop
11/09: Apsis
26/08: Gaia arrival in French Guiana
20/08: Gaia cartoons
11/07: Model Soyuz Fregat video
01/07: Acoustic Testing
21/06: SOVT
03/06: CU4 meeting #15
04/04: DPCC (CNES) 
26/03: Gaia artist impression 
11/02: Gaia payload testing  
04/01: Space flyby with Gaia-like data
2012
10/12: DPAC OR#2. Testing with Planck
05/11: Galaxy detection with Gaia
09/10: Plot of part of the GUMS-10 catalogue
23/07: "Gaia" meets at Gaia
29/06: The Sky as seen by Gaia
31/05: Panorama of BAM clean room
29/03: GREAT school results
12/03: Scanning-law movie
21/02: Astrometric microlensing and Gaia
03/02: BAM with PMTS
12/01: FPA with all the CCDs and WFSs
2011
14/12: Deployable sunshield
10/11: Earth Trojan search
21/10: First Soyuz liftoff from the French Guiana
20/09: Fast 2D image reconstruction algorithm
05/09: RVS OMA
10/08: 3D distribution of the Gaia catalogue
13/07: Dynamical Attitude Model
22/06: Gaia's view of open clusters
27/05: Accuracy of the stellar transverse velocity
13/05: Vibration test of BAM mirrors
18/04: L. Lindegren, Dr. Honoris Causa of the Observatory of Paris
19/01: Detectability of stars close to Jupiter
05/01: Delivery of the WFS flight models
2010
21/12: The 100th member of CU3
17/11: Nano-JASMINE and AGIS
27/10: Eclipsing binary light curves fitted with DPAC code
13/10: Gaia broad band photometry
28/09: Measuring stellar parameters and interstellar extinction
14/09: M1 mirror
27/08: Quest for the Sun's siblings
 
Please note: Entries from the period 2003-2010 are available in this PDF document.