# General quadrupolar statistical anisotropy: Planck limits

## Abstract

Several early Universe scenarios predict a direction-dependent spectrum of primordial curvature perturbations. This translates into the violation of the statistical isotropy of cosmic microwave background radiation. Previous searches for statistical anisotropy mainly focussed on a quadrupolar direction-dependence characterised by a single multipole vector and an overall amplitude g {sub *}. Generically, however, the quadrupole has a more complicated geometry described by two multipole vectors and g {sub *}. This is the subject of the present work. In particular, we limit the amplitude g {sub *} for different shapes of the quadrupole by making use of Planck 2015 maps. We also constrain certain inflationary scenarios which predict this kind of more general quadrupolar statistical anisotropy.

- Authors:

- Gran Sasso Science Institute (INFN), Viale Francesco Crispi 7, I-67100 L'Aquila (Italy)
- Institute for Nuclear Research of the Russian Academy of Sciences, Prospect of the 60th Anniversary of October 7a, 117312 Moscow (Russian Federation)
- Faculty of Engineering, Østfold University College, P.O. Box 700, 1757 Halden (Norway)
- National Institute of Chemical Physics and Biophysics, Rävala 10, 10143 Tallinn (Estonia)

- Publication Date:

- OSTI Identifier:
- 22679965

- Resource Type:
- Journal Article

- Resource Relation:
- Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 03; Other Information: Country of input: International Atomic Energy Agency (IAEA)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AMPLITUDES; ANISOTROPY; BACKGROUND RADIATION; DISTURBANCES; INFLATIONARY UNIVERSE; ISOTROPY; PERTURBATION THEORY; QUADRUPOLES; RELICT RADIATION; SPECTRA; UNIVERSE

### Citation Formats

```
Ramazanov, S., Rubtsov, G., Thorsrud, M., and Urban, F.R., E-mail: sabir.ramazanov@gssi.infn.it, E-mail: grisha@ms2.inr.ac.ru, E-mail: mikjel.thorsrud@hiof.no, E-mail: federico.urban@kbfi.ee.
```*General quadrupolar statistical anisotropy: Planck limits*. United States: N. p., 2017.
Web. doi:10.1088/1475-7516/2017/03/039.

```
Ramazanov, S., Rubtsov, G., Thorsrud, M., & Urban, F.R., E-mail: sabir.ramazanov@gssi.infn.it, E-mail: grisha@ms2.inr.ac.ru, E-mail: mikjel.thorsrud@hiof.no, E-mail: federico.urban@kbfi.ee.
```*General quadrupolar statistical anisotropy: Planck limits*. United States. doi:10.1088/1475-7516/2017/03/039.

```
Ramazanov, S., Rubtsov, G., Thorsrud, M., and Urban, F.R., E-mail: sabir.ramazanov@gssi.infn.it, E-mail: grisha@ms2.inr.ac.ru, E-mail: mikjel.thorsrud@hiof.no, E-mail: federico.urban@kbfi.ee. Wed .
"General quadrupolar statistical anisotropy: Planck limits". United States.
doi:10.1088/1475-7516/2017/03/039.
```

```
@article{osti_22679965,
```

title = {General quadrupolar statistical anisotropy: Planck limits},

author = {Ramazanov, S. and Rubtsov, G. and Thorsrud, M. and Urban, F.R., E-mail: sabir.ramazanov@gssi.infn.it, E-mail: grisha@ms2.inr.ac.ru, E-mail: mikjel.thorsrud@hiof.no, E-mail: federico.urban@kbfi.ee},

abstractNote = {Several early Universe scenarios predict a direction-dependent spectrum of primordial curvature perturbations. This translates into the violation of the statistical isotropy of cosmic microwave background radiation. Previous searches for statistical anisotropy mainly focussed on a quadrupolar direction-dependence characterised by a single multipole vector and an overall amplitude g {sub *}. Generically, however, the quadrupole has a more complicated geometry described by two multipole vectors and g {sub *}. This is the subject of the present work. In particular, we limit the amplitude g {sub *} for different shapes of the quadrupole by making use of Planck 2015 maps. We also constrain certain inflationary scenarios which predict this kind of more general quadrupolar statistical anisotropy.},

doi = {10.1088/1475-7516/2017/03/039},

journal = {Journal of Cosmology and Astroparticle Physics},

number = 03,

volume = 2017,

place = {United States},

year = {Wed Mar 01 00:00:00 EST 2017},

month = {Wed Mar 01 00:00:00 EST 2017}

}