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Table 2:

Brightness temperaturesa of the VLBI sources in Arp 299-A.
Source 8 April 2008 5 December 2008
name $S_\nu$($\mu $Jy) a(mas) b(mas) $T_{\rm B}$(K) $S_\nu$($\mu $Jy) a(mas) b(mas) $T_{\rm B}$(K)
A0 318 $\pm$ 42 ${\leq}2.8$ $\cdots$ $\cdots$ 446 $\pm$ 33 5.3 3.0 $1.8\times 10^{6}$
A1 855 $\pm$ 58 ${\leq}3.6$ $\cdots$ $\cdots$ 901 $\pm$ 51 2.1 1.8 $1.6\times 10^{7}$
A2 708 $\pm$ 53 ${\leq}2.5$ ${\leq}1.5$ ${\geq}1.3\times 10^{7}$ 713 $\pm$ 43 2.1 1.6 $1.4\times 10^{7}$
A3 398 $\pm$ 44 ${\leq}2.2$ $\cdots$ $\cdots$ 353 $\pm$ 30 $\leq6.5$ ${\leq}0.3$ ${\geq}1.2\times 10^{7}$
A4 558 $\pm$ 48 ${\leq}3.6$ ${\leq}2.3$ ${\geq}1.0\times 10^{8}$ 628 $\pm$ 40 ${\leq}2.8$ ${\leq}0.5$ ${\geq}3.0\times 10^{7}$
A5 278 $\pm$ 41 ${\leq}11.1$ ${\leq}1.2$ ${\geq}1.3\times 10^{6}$ 143 $\pm$ 25 $\cdots$ $\cdots$ $\cdots$
A6 208 $\pm$ 40 ${\leq}7.6$ ${\leq}1.4$ ${\geq}1.3\times 10^{6}$ $\leq$72 $\cdots$ $\cdots$ $\cdots$
A7 496 $\pm$ 46 ${\leq}2.5$ ${\leq}3.3$ ${\geq}4.0\times 10^{6}$ 468 $\pm$ 34 3.4 2.0 $4.6\times 10^{6}$
A8 226 $\pm$ 41 ${\leq}4.8$ $\cdots$ $\cdots$ 264 $\pm$ 27 ${\leq}3.3$ ${\leq}0.7$ ${\geq}7.6\times 10^{7}$
A9 294 $\pm$ 42 ${\leq}3.6$ ${\leq}4.4$ ${\geq}1.2\times 10^{6}$ 282 $\pm$ 28 $\cdots$ $\cdots$ $\cdots$
A10 550 $\pm$ 48 ${\leq}3.2$ ${\leq}3.9$ ${\geq}2.9\times 10^{6}$ 436 $\pm$ 32 $\cdots$ $\cdots$ $\cdots$
A11 300 $\pm$ 42 ${\leq}5.5$ $\cdots$ $\cdots$ 351 $\pm$ 30 ${\leq}4.5$ ${\leq}1.8$ ${\geq}2.0\times 10^{6}$
A12 449 $\pm$ 45 ${\leq}3.1$ ${\leq}3.7$ ${\geq}2.6\times 10^{8}$ 639 $\pm$ 40 2.3 1.5 $1.2\times 10^{7}$
A13 251 $\pm$ 41 ${\leq}3.3$ ${\leq}4.2$ ${\geq}1.2\times 10^{6}$ 118 $\pm$ 25 ${\leq}5.3$ $\cdots$ $\cdots$
A14 292 $\pm$ 42 ${\leq}5.0$ ${\leq}3.7$ ${\geq}1.1\times 10^{6}$ 260 $\pm$ 27 ${\leq}4.9$ $\cdots$ $\cdots$
A15 159 $\pm$ 40 $\cdots$ $\cdots$ $\cdots$ 304 $\pm$ 28 ${\leq}2.8$ ${\leq}1.6$ ${\geq}4.5\times 10^{6}$
A16 $\leq$117 $\cdots$ $\cdots$ $\cdots$ 147 $\pm$ 25 5.6 3.2 $5.5\times 10^{5}$
A17 $\leq$117 $\cdots$ $\cdots$ $\cdots$ 179 $\pm$ 26 7.3 3.9 $4.2\times 10^{5}$
A18 151 $\pm$ 40 $\cdots$ $\cdots$ $\cdots$ 129 $\pm$ 25 ${\leq}5.1$ ${\leq}5.5$ ${\geq}3.1\times 10^{5}$
A19 $\leq$117 $\cdots$ $\cdots$ $\cdots$ 191 $\pm$ 26 ${\leq}4.0$ ${\leq}2.0$ ${\geq}1.6\times 10^{6}$
A20 $\leq$117 $\cdots$ $\cdots$ $\cdots$ 146 $\pm$ 25 ${\leq}7.9$ ${\leq}3.5$ ${\geq}3.5\times 10^{5}$
A21 $\leq$117 $\cdots$ $\cdots$ $\cdots$ 133 $\pm$ 25 ${\leq}7.4$ ${\leq}2.9$ ${\geq}4.1\times 10^{5}$
A22 173 $\pm$ 40 $\cdots$ $\cdots$ $\cdots$ 217 $\pm$ 26 ${\leq}8.6$ ${\leq}4.3$ ${\geq}3.9\times 10^{5}$
A23 $\leq$117 $\cdots$ $\cdots$ $\cdots$ 137 $\pm$ 25 ${\leq}8.8$ ${\leq}2.9$ ${\geq}3.6\times 10^{5}$
A24 $\leq$117 $\cdots$ $\cdots$ $\cdots$ 166 $\pm$ 25 ${\leq}8.6$ ${\leq}7.0$ ${\geq}1.8\times 10^{5}$
A25 132 $\pm$ 40 $\cdots$ $\cdots$ $\cdots$ 209 $\pm$ 26 ${\leq}8.6$ ${\leq}4.4$ ${\geq}3.7\times 10^{5}$

a The brightness temperatures shown for the 5.0 GHz VLBI source components in Arp 299-A were calculated using the flux densities in Table 1 and the angular sizes quoted here. We derived the brightness temperatures from the general formula: $T_{\rm B} = (2~c^2/k)~B_\nu~\nu^{-2}$, where $B_\nu$ is the intensity, in erg s-1 Hz-1 str-1. Since $B_\nu$ depends on the measured flux density, $S_\nu$, and on the deconvolved angular size of each VLBI component (obtained by fitting them to elliptical Gaussians, characterized by their major and minor semi-axis, a and b). Therefore, the above formula can be rewritten as $T_{\rm B} = (2~c^2/k)~B_\nu~\nu^{-2} = 1.66$ $\times $ $10^{9}~~S_\nu ~ \nu^{-2} (a~b)^{-1}$, where $S_\nu$ is in mJy, $\nu$ in GHz, and a and b are in milliarcseconds, respectively.


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