Euclid preparation. LensMC, weak lensing cosmic shear measurement with
forward modelling and Markov Chain Monte Carlo sampling
Euclid Collaboration,G. Congedo,L. Miller,A. N. Taylor,N. Cross,C. A. J. Duncan,T. Kitching,N. Martinet,S. Matthew,T. Schrabback,M. Tewes,N. Welikala,N. Aghanim,A. Amara,S. Andreon,N. Auricchio,M. Baldi,S. Bardelli,R. Bender,C. Bodendorf,D. Bonino,E. Branchini,M. Brescia,J. Brinchmann,S. Camera,V. Capobianco,C. Carbone,V. F. Cardone,J. Carretero,S. Casas,F. J. Castander,M. Castellano,S. Cavuoti,A. Cimatti,C. J. Conselice,L. Conversi,Y. Copin,F. Courbin,H. M. Courtois,M. Cropper,A. Da Silva,H. Degaudenzi,A. M. Di Giorgio,J. Dinis,F. Dubath,X. Dupac,M. Farina,S. Farrens,S. Ferriol,P. Fosalba,M. Frailis,E. Franceschi,S. Galeotta,B. Garilli,B. Gillis,C. Giocoli,A. Grazian,F. Grupp,S. V. H. Haugan,M. S. Holliman,W. Holmes,F. Hormuth,A. Hornstrup,P. Hudelot,K. Jahnke,E. Keihänen,S. Kermiche,A. Kiessling,M. Kilbinger,B. Kubik,K. Kuijken,M. Kümmel,M. Kunz,H. Kurki-Suonio,S. Ligori,P. B. Lilje,V. Lindholm,I. Lloro,D. Maino,E. Maiorano,O. Mansutti,O. Marggraf,K. Markovic,F. Marulli,R. Massey,S. Maurogordato,H. J. McCracken,E. Medinaceli,S. Mei,M. Melchior,M. Meneghetti,E. Merlin,G. Meylan,M. Moresco,B. Morin,L. Moscardini,E. Munari,S. -M. Niemi,J. W. Nightingale,C. Padilla,S. Paltani,F. Pasian,K. Pedersen,W. J. Percival,V. Pettorino,S. Pires,G. Polenta,M. Poncet,L. A. Popa,L. Pozzetti,F. Raison,R. Rebolo,A. Renzi,J. Rhodes,G. Riccio,E. Romelli,M. Roncarelli,E. Rossetti,R. Saglia,D. Sapone,B. Sartoris,P. Schneider,A. Secroun,G. Seidel,S. Serrano,C. Sirignano,G. Sirri,L. Stanco,P. Tallada-Crespí,D. Tavagnacco,I. Tereno,R. Toledo-Moreo,F. Torradeflot,I. Tutusaus,E. A. Valentijn,L. Valenziano,T. Vassallo,A. Veropalumbo,Y. Wang,J. Weller,G. Zamorani,J. Zoubian,E. Zucca,A. Biviano,M. Bolzonella,A. Boucaud,E. Bozzo,C. Burigana,C. Colodro-Conde,D. Di Ferdinando,J. Graciá-Carpio,N. Mauri,C. Neissner,A. A. Nucita,Z. Sakr,V. Scottez,M. Tenti,M. Viel,M. Wiesmann,Y. Akrami,V. Allevato,S. Anselmi,C. Baccigalupi,M. Ballardini,S. Borgani,A. S. Borlaff,S. Bruton,R. Cabanac,A. Cappi,C. S. Carvalho,G. Castignani,T. Castro,G. Cañas-Herrera,K. C. Chambers,A. R. Cooray,J. Coupon,S. Davini,G. De Lucia,G. Desprez,S. Di Domizio,H. Dole,A. Díaz-Sánchez,J. A. Escartin Vigo,S. Escoffier,I. Ferrero,F. Finelli,L. Gabarra,J. García-Bellido,E. Gaztanaga,F. Giacomini,G. Gozaliasl,D. Guinet,A. Hall,H. Hildebrandt,S. Ilić,A. Jimenez Muñoz,S. Joudaki,J. J. E. Kajava,V. Kansal,D. Karagiannis,C. C. Kirkpatrick,L. Legrand,J. Macias-Perez,G. Maggio,M. Magliocchetti,R. Maoli,M. Martinelli,C. J. A. P. Martins,M. Maturi,L. Maurin,R. B. Metcalf,M. Migliaccio,P. Monaco,G. Morgante,S. Nadathur,L. Patrizii,A. Peel,A. Pezzotta,V. Popa,C. Porciani,D. Potter,M. Pöntinen,P. Reimberg,P. -F. Rocci,A. G. Sánchez,J. A. Schewtschenko,A. Schneider,E. Sefusatti,M. Sereno,P. Simon,A. Spurio Mancini,J. Stadel,J. Steinwagner,G. Testera,R. Teyssier,S. Toft,S. Tosi,A. Troja,M. Tucci,C. Valieri,J. Valiviita,D. Vergani
arxiv（2024）
引用0|浏览5
暂无评分
摘要
LensMC is a weak lensing shear measurement method developed for Euclid and
Stage-IV surveys. It is based on forward modelling to deal with convolution by
a point spread function with comparable size to many galaxies; sampling the
posterior distribution of galaxy parameters via Markov Chain Monte Carlo; and
marginalisation over nuisance parameters for each of the 1.5 billion galaxies
observed by Euclid. The scientific performance is quantified through
high-fidelity images based on the Euclid Flagship simulations and emulation of
the Euclid VIS images; realistic clustering with a mean surface number density
of 250 arcmin^-2 (I_ E<29.5) for galaxies, and 6 arcmin^-2
(I_ E<26) for stars; and a diffraction-limited chromatic point spread
function with a full width at half maximum of 0.^''2 and
spatial variation across the field of view. Objects are measured with a density
of 90 arcmin^-2 (I_ E<26.5) in 4500 deg^2. The total shear bias is
broken down into measurement (our main focus here) and selection effects (which
will be addressed elsewhere). We find: measurement multiplicative and additive
biases of m_1=(-3.6±0.2)×10^-3, m_2=(-4.3±0.2)×10^-3,
c_1=(-1.78±0.03)×10^-4, c_2=(0.09±0.03)×10^-4; a large
detection bias with a multiplicative component of 1.2×10^-2 and an
additive component of -3×10^-4; and a measurement PSF leakage of
α_1=(-9±3)×10^-4 and α_2=(2±3)×10^-4. When
model bias is suppressed, the obtained measurement biases are close to Euclid
requirement and largely dominated by undetected faint galaxies
(-5×10^-3). Although significant, model bias will be straightforward
to calibrate given the weak sensitivity.
