# Observed parity-odd CMB temperature bispectrum

## Abstract

Parity-odd non-Gaussianities create a variety of temperature bispectra in the cosmic microwave background (CMB), defined in the domain: ℓ{sub 1} + ℓ{sub 2} + ℓ{sub 3} = odd. These models are yet unconstrained in the literature, that so far focused exclusively on the more common parity-even scenarios. In this work, we provide the first experimental constraints on parity-odd bispectrum signals in WMAP 9-year temperature data, using a separable modal parity-odd estimator. Comparing theoretical bispectrum templates to the observed bispectrum, we place constraints on the so-called nonlineality parameters of parity-odd tensor non-Gaussianities predicted by several Early Universe models. Our technique also generates a model-independent, smoothed reconstruction of the bispectrum of the data for parity-odd configurations.

- Authors:

- Dipartimento di Fisica e Astronomia ''G. Galilei'', Università degli Studi di Padova, via Marzolo 8, Padova, I-35131 Italy (Italy)
- Centre for Theoretical Cosmology, Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA United Kingdom (United Kingdom)

- Publication Date:

- OSTI Identifier:
- 22382045

- Resource Type:
- Journal Article

- Resource Relation:
- Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 01; Other Information: Country of input: International Atomic Energy Agency (IAEA)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; LIMITING VALUES; PARITY; RELICT RADIATION; SIGNALS; TENSORS; UNIVERSE

### Citation Formats

```
Shiraishi, Maresuke, Liguori, Michele, and Fergusson, James R., E-mail: maresuke.shiraishi@pd.infn.it, E-mail: michele.liguori@pd.infn.it, E-mail: J.Fergusson@damtp.cam.ac.uk.
```*Observed parity-odd CMB temperature bispectrum*. United States: N. p., 2015.
Web. doi:10.1088/1475-7516/2015/01/007.

```
Shiraishi, Maresuke, Liguori, Michele, & Fergusson, James R., E-mail: maresuke.shiraishi@pd.infn.it, E-mail: michele.liguori@pd.infn.it, E-mail: J.Fergusson@damtp.cam.ac.uk.
```*Observed parity-odd CMB temperature bispectrum*. United States. doi:10.1088/1475-7516/2015/01/007.

```
Shiraishi, Maresuke, Liguori, Michele, and Fergusson, James R., E-mail: maresuke.shiraishi@pd.infn.it, E-mail: michele.liguori@pd.infn.it, E-mail: J.Fergusson@damtp.cam.ac.uk. Thu .
"Observed parity-odd CMB temperature bispectrum". United States.
doi:10.1088/1475-7516/2015/01/007.
```

```
@article{osti_22382045,
```

title = {Observed parity-odd CMB temperature bispectrum},

author = {Shiraishi, Maresuke and Liguori, Michele and Fergusson, James R., E-mail: maresuke.shiraishi@pd.infn.it, E-mail: michele.liguori@pd.infn.it, E-mail: J.Fergusson@damtp.cam.ac.uk},

abstractNote = {Parity-odd non-Gaussianities create a variety of temperature bispectra in the cosmic microwave background (CMB), defined in the domain: ℓ{sub 1} + ℓ{sub 2} + ℓ{sub 3} = odd. These models are yet unconstrained in the literature, that so far focused exclusively on the more common parity-even scenarios. In this work, we provide the first experimental constraints on parity-odd bispectrum signals in WMAP 9-year temperature data, using a separable modal parity-odd estimator. Comparing theoretical bispectrum templates to the observed bispectrum, we place constraints on the so-called nonlineality parameters of parity-odd tensor non-Gaussianities predicted by several Early Universe models. Our technique also generates a model-independent, smoothed reconstruction of the bispectrum of the data for parity-odd configurations.},

doi = {10.1088/1475-7516/2015/01/007},

journal = {Journal of Cosmology and Astroparticle Physics},

number = 01,

volume = 2015,

place = {United States},

year = {Thu Jan 01 00:00:00 EST 2015},

month = {Thu Jan 01 00:00:00 EST 2015}

}