# LACK OF ANGULAR CORRELATION AND ODD-PARITY PREFERENCE IN COSMIC MICROWAVE BACKGROUND DATA

## Abstract

We have investigated the angular correlation in the recent cosmic microwave background data. In addition to the known large-angle correlation anomaly, we find the lack of correlation at small angles with high statistical significance. We have investigated various non-cosmological contamination as well as the Wilkinson Microwave Anisotropy Probe (WMAP) team's simulated data. However, we have not found a definite cause. In the angular power spectrum of WMAP data, there exists anomalous odd-parity preference at low multipoles. Noting the equivalence between the power spectrum and the correlation, we have investigated the association between the lack of large-angle correlation and the odd-parity preference. From our investigation, we find that the odd-parity preference at low multipoles is, in fact, a phenomenological origin of the lack of large-angle correlation. Further investigation is required to find out whether the origin of the anomaly is cosmological or due to unaccounted systematics. The data from the Planck surveyor, which has systematics distinct from WMAP, will greatly help us to resolve its origin.

- Authors:

- Niels Bohr Institute and Discovery Center, Blegdamsvej 17, DK-2100 Copenhagen (Denmark)

- Publication Date:

- OSTI Identifier:
- 21587478

- Resource Type:
- Journal Article

- Journal Name:
- Astrophysical Journal

- Additional Journal Information:
- Journal Volume: 739; Journal Issue: 2; Other Information: DOI: 10.1088/0004-637X/739/2/79; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0004-637X

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ANGULAR CORRELATION; MULTIPOLES; PARITY; RELICT RADIATION; CORRELATIONS; ELECTROMAGNETIC RADIATION; MICROWAVE RADIATION; PARTICLE PROPERTIES; RADIATIONS

### Citation Formats

```
Kim, Jaiseung, and Naselsky, Pavel, E-mail: jkim@nbi.dk.
```*LACK OF ANGULAR CORRELATION AND ODD-PARITY PREFERENCE IN COSMIC MICROWAVE BACKGROUND DATA*. United States: N. p., 2011.
Web. doi:10.1088/0004-637X/739/2/79; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA).

```
Kim, Jaiseung, & Naselsky, Pavel, E-mail: jkim@nbi.dk.
```*LACK OF ANGULAR CORRELATION AND ODD-PARITY PREFERENCE IN COSMIC MICROWAVE BACKGROUND DATA*. United States. doi:10.1088/0004-637X/739/2/79; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA).

```
Kim, Jaiseung, and Naselsky, Pavel, E-mail: jkim@nbi.dk. Sat .
"LACK OF ANGULAR CORRELATION AND ODD-PARITY PREFERENCE IN COSMIC MICROWAVE BACKGROUND DATA". United States. doi:10.1088/0004-637X/739/2/79; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA).
```

```
@article{osti_21587478,
```

title = {LACK OF ANGULAR CORRELATION AND ODD-PARITY PREFERENCE IN COSMIC MICROWAVE BACKGROUND DATA},

author = {Kim, Jaiseung and Naselsky, Pavel, E-mail: jkim@nbi.dk},

abstractNote = {We have investigated the angular correlation in the recent cosmic microwave background data. In addition to the known large-angle correlation anomaly, we find the lack of correlation at small angles with high statistical significance. We have investigated various non-cosmological contamination as well as the Wilkinson Microwave Anisotropy Probe (WMAP) team's simulated data. However, we have not found a definite cause. In the angular power spectrum of WMAP data, there exists anomalous odd-parity preference at low multipoles. Noting the equivalence between the power spectrum and the correlation, we have investigated the association between the lack of large-angle correlation and the odd-parity preference. From our investigation, we find that the odd-parity preference at low multipoles is, in fact, a phenomenological origin of the lack of large-angle correlation. Further investigation is required to find out whether the origin of the anomaly is cosmological or due to unaccounted systematics. The data from the Planck surveyor, which has systematics distinct from WMAP, will greatly help us to resolve its origin.},

doi = {10.1088/0004-637X/739/2/79; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA)},

journal = {Astrophysical Journal},

issn = {0004-637X},

number = 2,

volume = 739,

place = {United States},

year = {2011},

month = {10}

}