Help on the Integration of $\int_0^{\infty} e^{-bx}\sin ax^2 \, \mathrm{d}x$.

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I have had the misfortune of coming across the following integral, for real $b$ and $a > 0$:

$$\int\limits_{0}^{\infty} e^{-bx} \sin\left(ax^{2}\right) \, \mathrm{d}x.\tag{1}$$

Naturally, I proceeded by taking (1) as equivalent to the imaginary part of the following integral:

$$\Im\int\limits_{0}^{\infty} e^{-bx} e^{iax^{2}}\,\mathrm{d}x.$$

Completing the square in the exponential yielded

$$ \Im \, {e}^{ib^{2}/4a}\int\limits_{0}^{\infty} \exp\left(ia\left[\, x + {ib \over 2a} \, \right]^{2} \right) \, \mathrm{d}x $$

whereupon I took out the term $e^{ib^{2}/4a}$ and factored the remaining polynomial. However, I am not sure if this is the right approach. I want to make it clear, though, that I am not looking for a complete evaluation, but rather advice on how to proceed.

Update:

Continuing from where I left off, I make the substitution $u = x + ib/2a$.

$$\Im \, e^{ib^2/4a} \int\limits_{c}^{\infty+c} e^{iau^2} \, \mathrm{d}u, \tag{2}$$

where $c=ib/2a$. Wolfram Alpha returns a mildy tame expression for this, namely

$$\int e^{iax^2} \, \mathrm{d}x = -\frac{e^{i3\pi/4}}{2}\sqrt{\frac{\pi}{a}} \; \mathrm{erfi}\left(e^{i\pi/4}\sqrt{a} \, x\right)+K,$$

for some constant $K$, and so we seek

$$-\frac{e^{i3\pi/4}}{2}\sqrt{\frac{\pi}{a}} \; \mathrm{erfi}\left(e^{i\pi/4}\sqrt{a} \, x\right) \Bigg|_{c}^{\infty+c},$$

in order to compute the remaining integral in (2). Evaluating this at the respective limits, however, does not seem very easy.

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If you are still looking for the answer to this, Mathematica 11.1 gives the answer in terms of FresnelC and FresnelS functions, however I managed to also tease a hypergeometric solution out. $$ I(a,b) = \int\limits_{0}^{\infty} e^{-bx} \sin\left(ax^{2}\right) \; dx $$

Take the Mellin transform of the integrand with respect to $b$, $$ \int_0^\infty b^{s-1}e^{-b x}\sin(a x^2) \; db = x^{-s}\Gamma(s)\sin(a x^2) $$ then integrate over $x$ assuming $a>0$ $$ \int_0^\infty x^{-s}\Gamma(s)\sin(a x^2) \; dx = \frac{1}{2}a^{\frac{1}{2}(s-1)}\cos\left(\frac{\pi(s+1)}{4}\right)\Gamma\left(\frac{1-s}{2}\right)\Gamma(s) $$ then perform the inverse Mellin transform (using Mathematica) $$ \frac{1}{2 \pi i} \int_{c-i \infty}^{c+i \infty} b^{-s}\frac{1}{2}a^{\frac{1}{2}(s-1)}\cos\left(\frac{\pi(s+1)}{4}\right)\Gamma\left(\frac{1-s}{2}\right)\Gamma(s) \; ds= I(a,b) $$ this gives $$ I(a,b) = \frac{-2b\;_1F_2\left(1\bigg|\frac{3}{4},\frac{5}{4}\bigg|-\frac{c^2}{4}\right)+\sqrt{2\pi a}\left(\cos(c)+\sin(c)\right)}{4a} $$ where $c=b^2/(4a)$. This seems to check out for a few numerical values.