Twist and Turn: Weak Lensing Image Distortions to Second Order

Details Twist and Turn: Weak Lensing Image Distortions to Second Order Twist and Turn: Weak Lensing Image Distortions to Second Order

2008-07-23

arxiv.org/abs/0807.3663v2

Astronomy and Astrophysics

Astrophysics

9 pages, 9 figures. Accepted by MNRAS; expands discussion of distortions and estimators

Scientific paper

We account for all the image distortions relevant to weak gravitational lensing to second order. Besides the familiar shear, convergence, rotation and flexions, we find a new image distortion with two distinct descriptions, the twist and the turn. Like rotation, this distortion is not activated gravitationally to first order, but will be activated by systematic effects. We examine the rotational properties of twist and turn, and their effect on images in real and shapelet space. We construct estimators for the new distortion, taking into account the centroid shift which it generates. We then use these estimators to make first constraints on twist using the STAGES HST survey; we find that the mean twist estimator is consistent with zero. We measure correlation functions for our twist estimator on the survey, again finding no evidence of systematic effects.

Affiliated with

Also associated with

No associations

Rating

Twist and Turn: Weak Lensing Image Distortions to Second Order does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Twist and Turn: Weak Lensing Image Distortions to Second Order, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Twist and Turn: Weak Lensing Image Distortions to Second Order will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-963